Owner manual

Watlow Controls 4 EHG CL User’s Guide
Alarm (flashing red)
Indicates that the process
temperature is higher than the
Limit High Set Point.
Alert (solid red)
Indicates that the process
temperature is higher than the
Closed Loop Set Point plus the
High Temperature Alert
Value.
Output (green)
Indicates that the output is on.
In Range (solid yellow)
Indicates that the process
temperature is in the normal
operating range (see figure at
right).
Up-Arrow Key
Increases the
displayed value.
Down-Arrow Key
Decreases the
displayed value.
Mode Key
Toggles the display between
the set point and process
temperature. Enters edited
values and advances
to the next prompt.
Optional Communications
Connectors
Optional Communications
Connectors
Flashing
Alert/Alarm (red) and
In Range (yellow)
If they are flashing together, that
indicates an Ambient Alarm
(controller temperature higher
than 85°C).
If they are flashing alternately, that
indicates a Health Check Error.
Alert/Alarm
In Range
Output
Alert/Alarm
In Range
Output
Alert/Alarm
In Range
Output
Alert/Alarm
In Range
Output
Alert/Alarm
In Range
Output
Alert/Alarm
In Range
Output
Alert/Alarm
In Range
Output
flashing
flashing
alternate
flashing
Control
Relay
Temperature
Alert Signal
off off
off on
off on
on on
off off Ambient Alarm
[Abt] 85°C
on on
off off Health Check Error
Normal Operating Range
Limit High Set Point [SLA]
Closed Loop Set Point
Closed Loop Set Point
Temperature
Alarm Hysteresis
Alarm Hysteresis
On-Off Hysteresis [HyS]
Closed Loop Set Point





Keys and Indicator Lights
EHG CL Error Codes
Display Description Possible Cause Corrective Action
Flashing
888
Limit error Sensor has exceeded SLA value or
open thermocouple
• Set SLA to correct Safety
Limit Value
• Check wiring of sensor
• Check sensor confi guration
Flashing
888
Control error Sensor has exceeded SLA value or
open thermocouple
• Set SLA to correct Safety
Limit Value
• Check wiring of sensor
• Check sensor confi guration
[Er3]
Limit Sensor Error Limit sensor reading out of range (<
-13 or > 640)
• Check wiring of sensor
• Check sensor confi guration
[Er4]
Control Sensor Error Control sensor reading out of range
(<-13 or > 640)
• Check wiring of sensor
• Check sensor confi guration
[Er5]
Limit Ambient Error Temperature at limit sensor cold junc-
tion (> 185 degrees)
• Check to be certain the EHG
CL is not in an ambient condi-
tion greater than 185 degrees
C
[Er6]
Control Ambient Error Temperature at control cold junction
(> 185 degrees)
• Check to be certain the EHG
CL is not in an ambient condi-
tion greater than 185 degrees
C
[ER9]
HMI Communications
Fault
Loss of communication between base
and display communications module.
See Also E20.
• Check connection between
EHG CL and display/commu-
nications module