Watlow Series 965 Controller

Er5 non-volatile memory verification error: 1. Power off and restart after 30 seconds to eliminate transient interference; 2. Enter the calibration menu and execute "rSt" to restore factory calibration; 3. If it is invalid, it is necessary to return to the factory to replace the memory

Er6 A/D conversion undercurrent (input voltage too low) 1. Check sensor wiring: thermocouple confirms polarity, RTD confirms lead resistance, process signal confirms signal source; 2. After replacing the sensor, press the MODE key to clear the error; 3. Confirm that the In parameter matches the input type

Er7 A/D conversion overflow (input voltage too high) 1. Check if the sensor is open circuit or polarity reversed (thermocouple); 2. Confirm whether the process signal exceeds the range (such as 4-20mA signal exceeding 20mA); 3. Confirm that the DIP switch is consistent with the In parameter

（2） Daily maintenance and noise suppression

Regular maintenance project

Monthly: Check whether the wiring terminals are loose (especially in vibration environments), whether the panel sealing ring is aging (NEMA 4X protection), and whether the sensor probe is scaled (affecting temperature measurement accuracy).

Quarterly: Clean the panel (using a soft cloth dipped in neutral cleaner), check the mechanical relay contacts (replace if there is erosion), calibrate the input accuracy (using a precision temperature source or signal source).

Every year: Conduct a comprehensive calibration of input/output, check power fuses (factory replaceable only), and evaluate the lifespan of output relays (mechanical relays are recommended to be replaced after 100000 cycles).

Noise suppression measures

Wiring: The distance between the input signal line (sensor line) and the power line and output line should be ≥ 305mm, and they should intersect at a 90 ° angle to avoid parallel wiring; Use shielded twisted pair cables (the shielding layer is only grounded at the controller end).

Load handling: Inductive loads (relay coils, solenoid valves) need to be connected in parallel with RC suppressors (Watlow 0804-0147-0000) to avoid electromagnetic interference during switching.

Grounding: Controller chassis grounding (through panel grounding), signal source and controller are grounded together to avoid grounding loops; An EMI filter can be installed on the power end (optional).