General safety recommendations

1. The instrument weighs about 5KG or more and is relatively long, so it is recommended to handle it gently when handling it. In addition to paying attention to personnel and instrument safety, attention should also be paid to the safety of surrounding items.

2. When using AC high-voltage power supply for instruments, please pay attention to electrical safety during installation and commissioning.

3. When using and maintaining on site, the principle of "no opening with power on" must be followed, and it is recommended to cut off the power for 10 minutes before operation.

When installing the instrument, please carefully read this manual and pay attention to any unsafe factors on site to avoid danger.

Before installation, it should be confirmed that the site and power supply meet the safe installation conditions, and that the instruments meet the requirements of the on-site process application conditions.

6. This instrument does not have any vulnerable parts and generally does not require spare parts. After correct installation and commissioning, it can operate reliably.

This instrument is maintenance free and does not require frequent maintenance. It can be debugged if necessary. If there is an instrument malfunction, please contact our service engineer and refer to section 7.9 of this user manual.

This manual is only used as a reference for the installation and debugging of this model of instrument, and does not have any technical or legal authority. In case of version changes, no further notice will be given. The final interpretation of the technical issues involved in this manual belongs to Tianjin Feite Measurement and Control Instrument Co., Ltd

Version Ver4.12.01.01.0

　　Chapter 1 Overview

1.1 Introduction

This manual is applicable to the GRLSTM FT8012 series universal point control instrument. The product is used for limit control and alarm, and is suitable for the vast majority of applications, hereinafter referred to as FT8012. Instruments are widely used in industrial and civilian fields, both indoors and outdoors. Compared to other forms of instruments, this instrument has no special requirements for on-site installation conditions. Figure 1.1 shows the schematic diagram of the FT8012 level gauge.

FT8012 is a universal point control instrument, which consists of an electronic unit, an explosion-proof housing, and rod or cable type sensing elements (also known as sensors or probes). The sensors can be made of various materials and can be installed as a whole or in separate units. Integrated installation refers to placing the electronic unit and sensing element in the same explosion-proof enclosure, while modular installation refers to placing the electronic unit and sensing element separately in two independent explosion-proof enclosures, connected by a specially designed cable from the manufacturer.

This instrument strictly follows the following international and Chinese standards and regulations in its design:

The safety design of this instrument complies with the IEC61010-1:2001 standard.

The electromagnetic compatibility design of this instrument complies with the IEC 61326:1998+Al standard.

The explosion-proof design of this instrument complies with:

GB 3836.1-2010 Explosive Atmosphere Part 1: General Requirements for Equipment

GB 3836.2-2010 Explosive Atmosphere Part 2: Equipment Protected by Flameproof Enclosures "d"

GB 3836.4-2010 Explosive Atmosphere Part 4: Equipment Protected by Intrinsic Safety Type "i"

GB 12476.1-2000 Electrical equipment for use in environments with combustible dust - Part 1: Electrical equipment protected by enclosures and restricted surface temperatures - Section 1: Technical requirements for electrical equipment

The protective design of the instrument casing complies with GB 4208-2008 Protection Class of Enclosures (IP Code)

1.2 Principle

Radio frequency admittance level control technology is a level control technology developed from capacitive level control technology, which has better anti hanging material (the material adhered to the sensor is called hanging material) performance, more reliable operation, more accurate measurement, and wider applicability. The meaning of "conduction" in "radio frequency admittance" is the reciprocal of impedance in electricity, which is composed of resistive, capacitive, and inductive components. "Radio frequency" refers to high frequency, so radio frequency admittance technology can be understood as a method of measuring admittance using high-frequency current.

The important difference between point RF admittance technology and capacitance technology is the use of three terminal technology and the diversity of measurement parameters. The measurement signal at the center end of the electronic unit is connected to the centerline of the coaxial cable, and then connected to the center end of the sensor. At the same time, the shielding layer of the coaxial cable is suspended at a very small and stable amplitude, but at the same potential, phase, frequency, and no direct electrical relationship with the measurement signal, that is, isolated from each other. Its effect is equivalent to that the measurement signal passes through a gain of "1" and a strong driving ability in-phase amplifier, and the output is connected to the shielding layer of the coaxial cable, and then connected to the shielding layer of the sensor. The ground wire is another independent conductor in the cable. Due to the above-mentioned relationship between the centerline and outer shielding of coaxial cables, there is no potential difference between the two, so no current flows through, that is, no current leaks out from the centerline, which is equivalent to no capacitance or capacitance equal to zero between the two. Therefore, the temperature effect of the cable and the installation of capacitors will not have any impact.

For the adhesive material on the sensor, which is called the hanging material influence problem, a new sensor structure with five concentric layers is adopted, as shown in Figure 1.2. The sensor structure: the innermost layer is the center probe, the middle is the shielding layer, and the outermost layer is the grounding installation thread, which is separated by an insulation layer. The situation is the same as with coaxial cables, where there is no potential difference between the center probe and the shielding layer. Even if the impedance of the hanging material on the sensor is small, no current will flow through. Electronic instruments only measure the current from the center of the sensor to the opposite tank wall (ground), because the shielding layer can hinder the current from flowing back to the container wall along the sensor. Therefore, the ground current can only pass through the end of the sensor and the measured material to the opposite container wall. That is, UA=UB, IAB=(UA-UB) × YL=0. Refer to Figure 1.3 for the equivalent schematic diagram of the measurement. Although there is a potential difference between the shielding layer and the container wall, and a current flows between them, this current is not measured and does not affect the measurement results. This protects the measuring end from the influence of hanging materials. Only when the material in the container does rise and come into contact with the central probe, can a measured current be formed between the central probe and the ground through the measured material. The instrument detects this current and generates an effective output signal.

Radio frequency admittance technology introduces measurement parameters other than capacitance, especially resistance parameters, which increases the signal-to-noise ratio of instrument measurement signals and significantly improves the resolution, accuracy, and reliability of instruments; The diversity of measurement parameters also greatly expands the reliable application areas of instruments.

Chapter 2 Performance Indicators

2.1 System performance indicators

Measurement equipment level: CAT II, transient rated voltage 2500V, cannot be used for levels other than CAT I and CAT II

Output: DPDT relay (double pole double throw) and alarm light output

Contact capacity: 250VAC: 1A inductive, 3A non inductive

Power supply: Universal power supply 30-265VAC, 50/60Hz and 21-35VDC automatic adaptation

Dissipative power: 2W

Resolution: 0.2pF or less

Setpoint accuracy:< 1mm (0.04 ″) or 0.5pF (conductive material)< 20mm (0.79 ") or 0.5pF (insulation material)

Load resistance: 500 Ω between center end and shield end, 50 Ω between shield end and ground

Alarm mode: It can be set on-site as HLFS (high-level alarm and fault insurance mode) or LLFS (low-level alarm and fault insurance mode)

Alarm light output: red light - level alarm; Green light - level normal; Yellow light - System malfunction alarm

Environmental temperature: T5:- 40～+70℃(-40～158℉); T6:- 40~+60 ℃ (-40~140 ℉) (The influence of medium temperature on ambient temperature cannot exceed the instrument's requirements for ambient temperature)

Storage temperature: -40~+85 ℃ (-40~185 ℉)

Alarm response time:<0.5 seconds

Alarm recovery delay: continuously adjustable from 2 to 25 seconds

Safety barrier: built-in current limiting and triple voltage limiting protection safety barrier

Electrostatic spark protection (for sensors): anti surge impact 1KV, anti-static 4KV/8KV

RF protection (built-in filter): The whole machine is tested by injecting current through a 10V/m electromagnetic field and a 3V/m electromagnetic field in space

Probe length: 0.25m (9.8 ") and 0.5m (19.7") (standard)

0.1m (3.9 ") to 20m (787.4") (optional)

Cable length: 5m (19.7 ") (standard), 0.1 (3.9")~50m (1968.5 ") (optional)>50m (1968.5")~100m (3937 ") (consult manufacturer)

Electrical interface: Dual M20 × 1.5 (optional 3/4 "NPT)

Process connection: NPT thread installation (standard, optional BSPT), flange installation (optional)

Shell material: die cast aluminum with epoxy coating

Shell protection: Compliant with IP67 protection standard

Explosion proof area level: Ex d ia[ia Ga] IIC T5/T6 Gb

Certification: PCEC/NEMSI. For other certification information, please consult the manufacturer

1.2 Probe indicators

　　Chapter 4 Installation

4.1 Unpacking

Carefully open the packaging box and remove the filling inside. Carefully check all items on the packing list, including instrument model, electronic unit and probe serial numbers, installation accessories, instructions, etc. If any errors, shortages or damages are found, please contact our company or local agent immediately. The packaging box is not recyclable.

4.2 Installation Requirements

The installation, use, and maintenance of the product should comply with the relevant provisions of the product installation, commissioning, and use instructions, GB50257 "Code for Construction and Acceptance of Electrical Equipment in Explosive and Fire Hazardous Environments", GB3836.15 "Electrical Equipment for Explosive Gas Environments Part 15: Electrical Installation in Hazardous Areas (excluding Coal Mines)", and GB3836.13 "Electrical Equipment for Explosive Gas Environments Part 13: Maintenance of Electrical Equipment for Explosive Gas Environments".

When installing instruments, they should be kept as far away as possible from vibration sources, high temperature environments, corrosive air, and any places that may cause mechanical damage. If the requirements cannot be met, please replace the instrument with a new component. The ambient temperature should be at: T5:- 40～+70℃(-40～158℉); T6:- Between 40 and+60 ℃ (-40 to 140 ℉) (the influence of medium temperature on ambient temperature cannot exceed the instrument's requirements for ambient temperature).

The instrument installation area requires lightning protection devices to prevent lightning strikes.

It is prohibited to use single component ambient temperature sulfurized sealant inside the instrument casing. This substance often contains acetic acid, which will corrode electronic components. Special two-component sealant (non corrosive) should be used.

The instrument casing is equipped with grounding terminals, and users should ensure reliable grounding during installation and use. When used for non-metallic cans, a standard ground should be provided on site and cannot be connected to the power ground.

The electrical interface should be equipped with cable sealing joints with a protection level of IP65 that meet the requirements of GB4208 standard to ensure reliable sealing and prevent damage to the instrument electronic unit caused by water ingress or other corrosive gases.

Do not disassemble the sensor or loosen the sealing nut to avoid probe leakage.

The installation of sensors should avoid material flow or inlet/outlet ports. If there are no other installation locations, protective covers or partitions should be added.

The installation of threads or flanges should be firmly connected to the container, reliably sealed, and have good electrical contact. Except for the connection, other parts of the sensor should not come into contact with the container to ensure good insulation.

When installing the sensor horizontally, it should be slightly tilted downwards at an angle of 10-20 °.

When installing hard rod sensors, the installation space should be considered, with a distance of at least 100mm from the tank wall. Cable sensors should be straightened after installation, with a distance of at least 300mm from the tank wall to avoid short circuits to the ground.

In situations where there is significant mixing, airflow, and material flow fluctuations inside the container to be tested, in addition to avoiding direct mechanical damage to the sensor, indirect mechanical damage such as long-term fatigue of the sensor material should also be considered. Therefore, it is recommended to install protective measures such as intermediate support and bottom anchor fixation for the sensor. Please note that the support and ground anchor should be insulated from the sensor, and the insulation material should be selected from materials with high insulation strength, low hardness, lubrication function, and no wear on the sensor (such as PTFE). If not, please consider replacing the sensor regularly to avoid sensor damage and chain loss.

When measuring large quantities of solid particles, the heavy hammer at the end of the sensor should be as high as possible above the cone angle of the silo. If it is necessary to enter the conical section, the maximum entry size should not exceed 20% of the diameter of the silo.

The non active section of the sensor should enter the tank at least 50mm. When the cable sensor is installed horizontally, the hard rod part entering the tank should not be less than 200mm, and when installed vertically, the hard rod part entering the tank should not be less than 100mm.

Instruments installed according to explosion-proof standards must be equipped with explosion-proof stuffing boxes or explosion-proof steel pipe sealing joints certified by GB3836.1 and GB3836.2 explosion-proof standards for electrical interfaces.

The ripple of 24VDC power supply shall not exceed 100mV.

The instrument connection cable shall comply with the requirements of IEC60245/60227 standard. It is recommended to use armored shielded 3-core cables with an outer diameter of no more than 12mm. The cable conductor material is copper, and the cross-sectional area of the conductor is 0.13-2.1mm2 (AWG14-26). The insulation strength of the cable is 1500V. Long distance unshielded cables cannot be used in parallel with AC power cables.

When using and maintaining on site, the principle of "no opening with power on" must be followed, and it is recommended to shut off the power for 10 minutes before operation.

4.6 Sensor wiring

Before opening the explosion-proof casing of the instrument in a hazardous environment, be sure to confirm that the instrument has been powered off and the relay terminals have been powered off for more than 10 minutes!!

The wiring between the integrated system sensor and the electronic unit has been connected by the manufacturer. If rewiring is required, please refer to Figure 4.5 for the overall wiring diagram. All round ended terminals of the overall line are connected to the sensor terminals; Connect the open end to the electronic unit terminal. Please ensure that the shielding end (red) of the overall wire is connected to the shielding end (marked DSH) of the electronic unit, and the center end (blue) is connected to the center end (marked CW) of the electronic unit. Due to the use of a metal base, the grounding wire of the electronic unit may not be connected. The center end (blue) of the overall sensor line is connected to the sensor center probe, and the shielding end (red) is connected to the sensor shielding layer.

The split line wiring method is shown in Figure 4.6, the split line wiring diagram. The terminal connection method is the same as the overall wire.

4.7 Relay wiring

Before opening the explosion-proof casing of the instrument in a hazardous environment, make sure that the instrument has been powered off and the relay terminals have been powered off for more than 10 minutes!! Before connecting the relay, be sure to confirm that the power cord is not supplying power and that the relay terminals have been disconnected!!

Each wiring connected to the explosion-proof enclosure in hazardous environments must be equipped with certified sealing fittings, such as explosion-proof stuffing boxes or explosion-proof steel pipe sealing joints.

The relay has a double pole double throw (DPDT) output and serves only as a switch, unable to directly drive high-power devices. All control signals are output from the terminal block located in the upper right corner of the front of the electronic unit. Figure 4.7 Relay Contact Diagram.

Relay wiring method:

1. Unscrew the upper cover of the housing and insert the signal lead through the explosion-proof packing box or explosion-proof steel pipe sealing joint from the right inlet into the housing.

2. Remove the wire protection box from the unit. (Please keep the 2 screws that have been removed properly)

3. Connect the leads to the corresponding wiring terminals on the upper part of the unit and confirm that they are correct.

4. Return the wire protection box to its original position.

5. Adjust the lead length to the appropriate size and tighten the explosion-proof stuffing box or explosion-proof steel pipe sealing joint.

6. Tighten the upper cover of the housing.

The instrument adopts a conventional logic method. When the red light is on, the relay is in a power-off state (reset). Usually, this state unit indicates an alarm (when the power is off, the relay is also in a power-off state, and the red light is not on).

The high-level alarm method is usually used for high-level alarms. Normally, the sensor does not touch the material, that is, the material level is lower than the sensor position.

The low-level alarm method is usually used for low-level alarms. Normally, the sensor contacts the material, that is, the material level is higher than the sensor position.

As shown in Figure 4.8, the schematic diagram of the relay contact position during normal operation. Sometimes the high and low position alarm method is also used for on-site selection of whether the alarm is normally open or normally closed. But it is not recommended to use it this way because it loses the fault insurance function.

Regarding fault insurance, in the event of an unexpected malfunction of the instrument (such as power failure or short circuit to ground at the shielding end), the transmitter is set to emit a high-level alarm signal when a high-level fault alarm is triggered. Set the transmitter to emit a low-level alarm signal when a low-level fault alarm is triggered. This means that the instrument is in an alarm state when there is a power outage.

The relay contact position shown on the instrument label is the relay contact position when the instrument output is in normal state (green light).

Note: There is no absolute fault insurance, and the fault insurance design of this product only covers most important parameters.

4.8 Power Wiring

Before opening the explosion-proof casing of the instrument, make sure that the power cord is not supplying power and the relay terminal has been disconnected for more than 10 minutes!! Before wiring the power supply, make sure that the power cord is not supplying power and the relay terminals are disconnected!!

Each wiring connected to the explosion-proof enclosure in hazardous environments must be equipped with certified sealing fittings, such as explosion-proof stuffing boxes or explosion-proof steel pipe sealing joints.

All power wiring is connected to the terminal board on the left side of the front of the electronic unit. As shown in Figure 4.7, the power supply and relay contact diagram.

Wiring method of power cord:

1. Unscrew the upper cover of the housing and insert the power cord through the explosion-proof packing box or explosion-proof steel pipe sealing joint from the left inlet into the housing.

2. Remove the wire protection box from the unit. (Please keep the 2 screws that have been removed properly)

3. Connect the leads to the corresponding wiring terminals on the upper part of the unit and confirm that they are correct.

4. Return the wire protection box to its original position.

5. Adjust the length of the power cord to the appropriate size and tighten the explosion-proof stuffing box or explosion-proof steel pipe sealing joint.

6. Tighten the upper cover of the housing.

　　Chapter 5 Function Settings

5.1 Working point setting

As shown in Figure 4.7, the power supply and relay contact diagram, where the "SETPOINT" potentiometer is a working point setting potentiometer used to adjust the position of the electronic unit relay action. Clockwise rotation of the potentiometer raises the relay working point, and counterclockwise rotation lowers it. The green LED light indicates that the electronic unit relay is powered on, indicating that it is in a normal state, while the red LED light indicates that the electronic unit relay is powered off and reset, indicating that it is in an alarm state.

5.2 Setting of high and low alarm modes

The high and low level alarm mode indicates whether the alarm is triggered when the material is above or below the set point. High Level Alarm Mode (HLFS) means that the relay will alarm when the material exceeds the set point. Low level alarm mode (LLFS) means that the relay alarms when the material is below the set point. When placing an order, the instrument should also set high and low level alarm modes according to the user's requirements (unless otherwise specified, generally set as HLFS). The high and low alarm modes can also be set on site by selecting the port for the fault protection mode on the top of the instrument electronic unit (toggle switch 1st position) and selecting the switch position. Figure 5.1 High and Low Level Alarm Modes

5.3 Delay Mode Setting

Delay adjustment is located on the top surface of the electronic unit, labeled as' TIME DELAY '. There is a potentiometer for delay adjustment. Turning the potentiometer adjustment knob clockwise can extend the delay time. The delay function is only effective for the process of the electronic unit transitioning from an alarm state to a normal state, that is, the electronic unit always outputs an alarm signal as soon as possible, regardless of the delay setting.

This potentiometer is invalid for electronic units without delay function.

5.4 Range setting

In most cases, the range is set to the second gear, and the factory settings are also in this position.

The measuring range is set at the "RANGE" on the top of the electronic unit, and the second, third and fourth positions of the toggle switch are moved. When measuring materials with different sensor lengths, measuring ranges and different insulation levels or materials with different conductivity, the toggle switches of different positions are moved to the top, and the other two switches are moved to the bottom.

Relationship between material conductivity and gear position:

Level 2: Sensor length less than 300mm or highly insulating material, such as plastic powder or foam plastic particles;

Level 3: Sensor length less than 3000mm or measuring general insulation and conductive materials;

Level 4: Sensor length greater than 3000mm or measuring semiconductor or conductive materials;

　　Chapter 6 Debugging

Before opening the explosion-proof casing of the instrument in a hazardous environment, make sure that the instrument has been powered off and the relay terminals have been powered off for more than 10 minutes!!

6.1 Startup

Before powering on, carefully check the power wiring. Please refer to section 4.10 for details. During the debugging process, it is necessary to open the instrument casing. At this time, when the instrument is live, personal safety must be taken into account. And the relay terminal requires power-off!!

After completing the calibration, the casing must be reinstalled. Each wiring connected to the explosion-proof enclosure in hazardous environments must be equipped with certified sealing fittings, such as explosion-proof stuffing boxes or explosion-proof steel pipe sealing joints.

6.2 Factory calibration

All FT8012 products are set by the manufacturer to be suitable for measuring aqueous solutions of conductive materials, so if used in such situations, no further calibration is required.

If the calibration is damaged, please recalibrate. If it is an insulation material, please refer to Figure 6.1 Calibration of Insulation Material 1 and calibrate according to 6.3. If it is a conductive material, please calibrate according to 6.4.

6.3 Calibration of Insulation Materials (Taking High Level Alarm Mode as an Example)

A. Ensure that the material is under the sensor, i.e. not in contact with the material

B. Rotate the set point potentiometer counterclockwise to the endpoint

C. Adjust the knob clockwise until the relay is just in motion (i.e. the LED green light is on), as shown in Figure 6.1 Calibration of Insulation Material 1

D. Raise the level to cover the sensor. Refer to Figure 6.2 for the calibration of insulation material 2 (at this time, the LED red light is on).

E. Always pay attention to adjusting the position of the tool

F. Slowly adjust the knob clockwise until the relay acts again (i.e. the LED green light is on) or turn it clockwise to the end point. Record the number of turns twisted.

Figure 6.2 Calibration of Insulation Materials 2

G. Rotate the knob counterclockwise and adjust the number of turns to half of the previously recorded number.

H. Calibration completed. For recalibration, the recorded 1/2 of the number of turns is the "preload".

Attention: If the number of adjustment cycles corresponding to the contact and non-contact materials of the sensor is less than 1 cycle, please consult our company.

6.4 Calibration of Conductive Materials (Taking High Level Alarm Mode as an Example)

A. Ensure that the material is under the sensor, i.e. not in contact with the material. Refer to Figure 6.1 for Calibration 1 of Insulation Materials.

B. Rotate the set point potentiometer counterclockwise to the endpoint.

C. Adjust the knob clockwise until the relay operates precisely. (i.e. the LED green light is on).

D. Slowly adjust the knob clockwise by 2-5 turns, and if the material has good conductivity, turn it a few more turns. For conductive materials like water, the potentiometer can be directly rotated to the end.

6.5 Pre calibration (also known as empty warehouse calibration) (this calibration is based on high-level alarm mode as an example)

A. Ensure that the container for installing the sensor on the material is empty and the sensor installation is correct.

B. Rotate the set point potentiometer counterclockwise to the endpoint.

C. Adjust the knob clockwise until the relay operates precisely. (i.e. the LED green light is on).

D. Slowly adjust the knob clockwise by 3/4 turn. This 3/4 turn is called preload. If the insulation strength of the material is high, it can be 1/2 turn. Generally, the insulation strength is 3/4 turn. If the conductivity of the material is good, rotate it a few more turns.

　　Chapter 7 Troubleshooting

7.1 Overview

The FT8012 instrument is designed to be maintenance free for several years and generally does not require regular or planned maintenance. This series of products does not require special spare parts. But if the application is extremely demanding, it is best to have a spare electronic unit to avoid inconvenience caused by instrument damage. Damaged units should be returned to the factory for repair.

The instruments are carefully manufactured and undergo strict quality inspection. Nevertheless, any instrument is prone to errors, and rich engineering experience tells us that a completely independent backup system is essential to avoid dangerous situations caused by one or several devices not working.

If your instrument malfunctions, the entire system can be disassembled into components for inspection. The following troubleshooting steps apply to the FT8012 level gauge. If the exact fault cannot be identified, please contact your local agent or directly contact us.

Before opening the explosion-proof casing of the instrument in a hazardous environment, make sure that the instrument has been powered off and the relay terminals have been powered off for more than 10 minutes!!

7.2 Inspection of Electronic Units

When conducting inspections of electronic units, it is important to ensure personal safety as the inspection requires power on, and the relay terminals must be powered off!!

A. Refer to Figure 7.1 for the inspection of the electronic unit. Disconnect the wiring between the sensor and the electronic unit, and disconnect the blue and red terminals from the center and shield ends, respectively. But do not disconnect the power cord.

B. Connect a capacitor between 1 and 10 pF between the center end and the ground end.

C. Starting from the counterclockwise position of the set point knob, slowly adjust it clockwise with a calibration screwdriver until the relay is activated.

D. Rotate counterclockwise from this point until the relay operates again. Pay attention to the difference in the number of turns of the potentiometer between the two actions of the relay. If the number of turns is less than 1/4 turn, the instrument is working properly.

If the instrument is not working properly, please consult our company's service department.

7.3 Inspection of Sensors

A. Disconnect the shielding end (red) and center end (blue) of the sensor, as shown in Figure 7.1 for inspection of the electronic unit.

B. If there is a hanging material on the sensor, use a multimeter ohm range to measure the following resistance values: see Figure 7.2 Sensor Inspection

The resistance between the center end and the shielding end

Resistance between shielding end and ground end

Measure the following voltages using a multimeter in DC voltage range:

Voltage values at the center and shielding ends

The voltage values between the shielding end and the ground end

C. The resistance value in step B should be greater than the following values:

Center end and shielding end 500 Ω

Shielding end and ground end 150 Ω

The voltage value in step B should be less than the following values:

Center end and shielding end 100mV

Shielded end and ground end 200mV

D. If the resistance value is less than these two values or the voltage value is greater than these two values, please clear the hanging material on the sensor and repeat operation B.

E. When there is no hanging material on the sensor, measure the following resistance values with a multimeter in the ohm range:

The resistance between the center end and the shielding end

Resistance between shielding end and ground end

Measure the following voltages using a multimeter in DC voltage range:

Voltage values at the center and shielding ends

The voltage values between the shielding end and the ground end

F. If both of the above resistance values are less than 1M Ω or the voltage value is greater than 200mV, please contact us

7.4 Inspection of Relay Circuit

When checking the relay circuit, be sure to pay attention to personal safety as the inspection requires power on!!

A. The relay circuit consists of two sets of terminal blocks and a double pole double throw relay.

B. Adjust the instrument as described in section 5.1.

C. When the background noise is not too loud, a "cata" sound will be heard when the relay is activated. Use an ohmmeter to check if the relay contacts are activated.

D. The difficulty in debugging is often caused by incorrect connections between relay terminals and alarm devices or other equipment on the cabinet. Please check the relay wiring according to Figure 4.8 and confirm that the high and low position alarm methods shown in Figure 5.2 are in the correct position when the instrument is working.

7.5 Inspection of Connecting Cables

Remove the cable from the unit and probe, and use a multimeter to measure the following resistance values in ohms range to determine if they match the internal resistance values in parentheses.

Refer to Figure 7.3 for the overall line outline and Figure 7.4 for the split line outline

Overall line measurement:

Resistance value between two blue forks (less than 2 ohms)

Resistance value between two red forks (less than 2 ohms)

Resistance between blue fork and red fork (greater than 100M)

Measurement of split cable

Resistance value between two blue forks (less than 10 ohms)

Resistance value between two red forks (less than 10 ohms)

Resistance value between two green forks (less than 10 ohms)

Resistance between forks of three colors (greater than 100M)

7.6 Troubleshooting of Other Malfunctions

Note: The solutions marked with "*" can only be completed by the manufacturer or agent.

7.7 Manufacturer support

If your product malfunctions and the troubleshooting methods in the "FT8012 Product User Manual" still cannot solve the problem:

1. Please contact the local agent or business manager directly

2. Contact our company's service department directly at (86-22-)

3. Please fax the following information to our company's service department, fax: (86-22-)

Order number: Instrument serial number:

Sensor element serial number and length: Cable length (split):

Medium: Temperature: Pressure: Stirring:

Main fault description:

Fault detection method:

7.8 Equipment Repair

In order to provide better service to users, any instrument sold by our company can be repaired. Before repair, it must be confirmed by our company (equipment measuring toxic and harmful media is not accepted for repair), and a repair permit number must be obtained. Any repaired equipment must include the above and the following information:

Repair permit number:

Reason for repair:

Contact person:

Shipping destination address:

In order to facilitate the return of the repaired equipment to your location, you must attach a purchase voucher during the repair process. If your equipment is within the warranty period, you do not need to pay for the repair fee. Please pay the shipping fee in advance when repairing.

To improve repair speed, our company usually adopts the method of exchange. If you still want your original equipment, please indicate "Do not exchange" on the repair order; Usually, companies stock standard electronic units.

Please send the repaired equipment back to the following address:

Company Name: Tianjin Feite Measurement and Control Instrument Co., Ltd

Company Address: 1st Floor, Unit D, Building 1, No. 13 Ziyuan Road, Nankai District, Tianjin

Postal Code: 300384

7.9 On site service

Our service personnel can provide you with instrument debugging, troubleshooting, and instrument personnel training, with hourly charges. Please contact our service department for details.

Contact phone number: (86-22-)

7.10 User Training

The company regularly holds customer training courses at designated locations, composed of our engineers and experts, who can provide detailed information on all aspects of level measurement, including principles and practical operations.

If you need detailed information, please contact our company through the following methods:

Phone: (86-22-)

Fax: (86-22-)

Website: H ttp://www.futureinstr.com

Email: info@futureinstr.com

yuanjing@futureinstr.com