Watlow PM PLUS™ 6 • 98 • Chapter 8: Features
Silencing Alarms
If silencing is on you can disable the alarm output while the controller is in an alarm state. The process
value or temperature has to enter the normal operating range beyond the hysteresis zone to activate the
alarm output function again. An active message, such as an alarm message, will cause the display to toggle
between the normal settings and the active message on the Home screen display.
To enable alarm silencing, go to Operations — Setup — Alarm — Alarm [1,2,3,4] — Silencing — [Off,On],
NOTE: If silence is on, and you silence with Home Key, the message is cleared, but the warning
symbol remains.
Blocking Alarms
Blocking allows a system to warm up after it has been started up. With blocking on, an alarm is not trig-
gered when the process temperature is initially lower than the low set point or higher than the high set
point. The process temperature has to enter the normal operating range beyond the hysteresis zone to
activate the alarm function. If the PM PLUS has an output that is functioning as a deviation alarm, the alarm
is blocked when the set point is changed, until the process value re-enters the normal operating range.
To enable alarm silencing, go to Operations — Setup — Alarm — Alarm [1,2,3,4] — Blocking — and then
select the desired blocking option: [Off,Startup,Set Point,Both],
Current Sensing
The measurements taken for current sensing use the AC Line Frequency setting found at Operations —
Global — AC Line Frequency — [50Hz,60Hz]. If this setting does not represent the incoming line frequency
of this controller the readings will be in error and may appear to be frozen.
If an alarm is configured to monitor current, the low alarm is effective only when the current level is
equal to or greater than 2mA. If there is no current present, the low alarm will not be activated.
Open and Shorted Load Circuit Detection
A Current Error C.Er (Operations Page, Current Menu) can detect either an open or shorted load condition.
A shorted condition would be present if the control is calling for 0% power while current is detected as
flowing through the current transformer. Conversely, an open condition would be present when the control
is calling for power with no current flow detected through the transformer.
A Heater Error indicates if the load current flow is within the specified limits set by the user through the
Current Set Points (High Set Point and Low Set Point) at Operations — Current.
Read and monitor the real-time current level through the Load Current RMS prompt while the most recent
faults can be read via the Current Error and Heater Error prompts. All of these prompts can be found in the
Operations Page under the Current Menu.
To Next Page
Loading...
Need help?
General
