1、 Installation and wiring

1. Location Selection
   • Stay away from sources of interferenceAvoid approaching strong electromagnetic field equipment (such as transformers and motors) to prevent measurement errors caused by signal interference.
   • Ventilation and heat dissipationInstalled in a well ventilated area to avoid high temperature environments affecting sensor accuracy (such as installing a heat shield near an industrial oven).
   • Avoid blind spotsAvoid installing in ventilation blind spots or areas with large temperature gradients (such as directly below the air conditioning outlet).
2. Wiring specifications
   • Power matchingEnsure that the power supply voltage is consistent with the nominal voltage of the thermostat (e.g. 24V DC thermostat cannot be connected to 220V AC).
   • Wire diameter selectionChoose the appropriate wire diameter based on the load current (e.g. 5A load requires ≥ 1mm ² copper wire) to avoid overheating of the circuit.
   • Separation of strong and weak currentsThe signal line and power line should be wired separately with a spacing of ≥ 5cm to prevent electromagnetic interference.
   • grounding protectionMetal shell equipment must be reliably grounded with a grounding resistance of ≤ 4 Ω.

2、 Usage and Debugging

1. Parameter Settings
   • temperature rangeSet upper and lower limits according to process requirements (such as fermentation tank temperature ± 0.5 ℃ in the pharmaceutical industry).
   • Return difference settingReasonably set the hysteresis (such as ± 1 ℃) to avoid frequent start stop and shorten the equipment life.
   • sensor calibrationRegularly calibrate with a standard thermometer (recommended every six months), and adjust or replace if the error exceeds ± 1 ℃.
2. operation monitoring
   • abnormal alarmEnable alarm functions such as overheating, wire breakage, and sensor failure, with the alarm threshold set 5% lower than the process upper limit.
   • data recordingKey equipment needs to be equipped with data recorders, with recording intervals of ≤ 1 minute, for easy fault tracing.
   • Load matchingThe contact capacity of the relay should be ≥ 1.5 times the load current (e.g. 15A contact for 10A load).

3、 Maintenance and upkeep

1. routine inspection
   • Visual inspectionCheck the shell for damage and loose wiring terminals every month.
   • Functional testingSimulate overheating conditions every quarter to verify alarm and shutdown functions.
   • Sensor cleaningWipe the surface of the sensor with a soft cloth to avoid oil and water stains from adhering.
2. regular maintenance
   • calibration cycleIndustrial grade thermostats are calibrated once a year, while laboratory grade thermostats are calibrated every six months.
   • Component replacementRelay contact oxidation needs to be polished or replaced, and capacitor capacity attenuation exceeding 20% needs to be replaced.
   • software upgradeIntelligent temperature controllers require regular firmware updates to fix known vulnerabilities.

4、 Safety and Emergency Response

1. safety protection
   • overload protectionInstall fuses or circuit breakers on the load side, with a rated current of 1.2-1.5 times the load current.
   • Explosion-proof requirementsExplosion proof temperature controllers (Ex d Ⅱ CT6 grade) should be used in flammable and explosive places.
   • Redundant designKey equipment adopts dual temperature controllers as backup for each other, with a master-slave switching time of ≤ 5 seconds.
2. emergency response
   • Overtemperature disposalWhen overheating occurs, immediately cut off the main power supply and start the backup cooling system.
   • Sensor malfunctionActivate the backup sensor or manual mode, and control according to the preset curve.
   • Fire responseThe temperature controller box is equipped with an automatic fire extinguishing device (such as heptafluoropropane) with a fire extinguishing concentration of ≥ 7%.

5、 Special scenario precautions

1. high-temperature environment
   • Select high-temperature resistant temperature controllers (working temperature ≥ 85 ℃), and use high-temperature resistant materials (such as PTFE) for sensor cables.
   • Add a cooling fan and ensure that the surface temperature of the thermostat is ≤ 65 ℃.
2. humid environment
   • Protection level ≥ IP65, installed inside a sealed box, with desiccant placed inside the box.
   • Coat the wiring terminals with moisture-proof silicone grease and check the insulation resistance (≥ 1M Ω) monthly.
3. Corrosive environment
   • The shell is made of 316L stainless steel or engineering plastic, and the sensor is equipped with a corrosion-resistant sheath.
   • Regularly inspect the sealing ring and replace it immediately if it has aged or deformed.