Manual
Watlow Series PD ■ 19 ■ Chapter 3 Indicator Lights
The Series PD controller may have up to nine LED indicator lights to help you monitor the
status of input power, Ethernet functions, input errors and outputs status. These LEDs can
provide a quick visual indication of basic controller functions. 
PD
PID Controller
Power
Ethernet Link
Ethernet Activity
1
2
3
4
1
2
Input Error
Input Error
Output
Output
Output
Output
Address
Power 
Green light stays lit when the 
power is on. 
• If not lit or flashing, check 
your power source.
Ethernet Link:
Green light is lit if the Ethernet 
cable is correctly wired and 
connected to a 10BaseT port. 
• If not lit, check for the correct 
RJ-45 cable and switch/hub speed.
Ethernet Activity 
Green light is lit when commun-
ication activity occurs.
(1) Input Error 
Red light is lit if there is a sensor 
problem on Input 1. Lights momen-
tarily after power up. 
• If it stays lit: 
- Verify the sensor wiring, polarity 
and function. 
- Rewire or replace as necessary.
(2) Input Error 
Red light is lit if there is a sensor 
problem on Input 2. Lights momen-
tarily after power up. 
• If it stays lit: 
- Verify the sensor wiring, polarity 
and function. 
- Rewire or replace as necessary.
(1) Output 
Red light is lit or flashes when 
control Output 1 is active. If it does 
not light up, the output is not active. 
The output may be configured as an 
event (alarm) or control.
(2) Output 
Red light is lit or flashes when 
control Output 2 is active. If it does 
not light up, the output is not active. 
The output may be configured as an 
event (alarm) or control.
(3) Output 
Red light is lit or flashes when 
control Output 3 is active. If it does 
not light up, the output is not active. 
The output may be configured as an 
event (alarm) or control.
(4) Output 
Red light is lit or flashes when 
control Output 4 is active. If it does 
not light up, the output is not active. 
The output may be configured as an 
event (alarm) or control.
Address Field
Record the unit's Device Name
in erasable marker here. For example,
PD012345.
Figure 18 — Series PD LED Indicator Lights
Indicator Lights
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