Watlow PM PLUS ™ PID/Integrated Limit Controller

Modbus RTU baud rate 1200-19200bps, addresses 1-247, supports function codes 03 (read register), 06 (write single register), and 16 (write multiple registers) to connect PLC or HMI and achieve multi device networking

EtherNet/IP supports DHCP or fixed IP, with a maximum of 40 members in the I/O assembly, capable of real-time transmission of process values and control commands in industrial Ethernet environments, requiring high-speed data exchange

DeviceNet node address 0-63, baud rate 125/250/500kbps, supports implicit/explicit communication, compatible with Rockwell and other brands of PLCs, suitable for device layer networking

（2） Remote configuration process (using Bluetooth as an example)

Download the EZ-LINK app (supports iOS/Android), turn on the controller Bluetooth ("Setup - Global - Bluetooth" set to "On").

Search for and pair devices within the application, enter "Parameter Configuration", and modify input types (such as thermocouple J-type), PID parameters, and alarm thresholds.

Save parameters to the device or local (supports 2 sets of user configurations), monitor process values and output power in real-time during operation, and receive alarm push notifications.

Maintenance and troubleshooting

（1） Daily maintenance

Regular inspection: monthly cleaning of panels and heat sinks, quarterly tightening of terminals (to avoid cold flow loosening), annual calibration of input/output (via the "Factory Calibration" menu, requiring a standard signal source).

Parameter backup: Save the configuration to User Set 1/2 through "Setup - Global - Save Settings As" to avoid resetting after a malfunction.

Firmware Upgrade: Supports firmware upgrade through communication port. The latest firmware and upgrade tool must be downloaded from the Watlow official website. Power off is prohibited during the upgrade process.

（2） Common fault handling

Possible causes and solutions for the fault phenomenon

No display/output power supply not connected, fuse burned out, loose terminals. Check the power supply voltage and fuse (Slot C terminal 98/99), re tighten the terminals, and replace the fuse (matching model required)

The temperature cannot reach the set value due to heating output fault, improper PID parameters, sensor error check output wiring and load, re perform automatic tuning, calibrate sensor offset ("Setup - Analog Input - Calibration Offset")

Alarm cannot be cleared. Alarm not cleared, alarm locked, parameter error confirmation process value returned to safe range. Clear it through "Operations - Alarm - Clear Alarm" and check the alarm type configuration

Communication failure: Address/baud rate mismatch, wiring error, interference with unified device communication parameters. Check RS-485 polarity (A/B lines), route away from power lines, and add terminal resistors