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Resetting the overload is accomplished by
pushing in the blue Differential Overloads
button on the right front face of the device,
and rotating it approximately an eighth of a
turn clockwise.
Adjustment of the overload setpoint is
performed using the blue dial on the left front
face of the device.
Once the overload has been reset, individual
pump faults require turning the individual
pump switch to the OFF position, and then
back ON (re-arming).
High Pump Temperature (Optional)
High pump temperature utilizes a temperature
probe inserted into the pump discharge piping.
The probe trips when the water temperature
reaches 120°F, and then immediately shuts
down the pump. The green light above the
pump switch flashes, indicating which pump
has shut down. Go to "Alarms," and the
display should show that an "Individual Pump
fault" has occurred.
The temperature probe automatically resets at
105°F. At that time, the pump can be re-
armed, and pump operation can continue.
NOTE:
If the pump continues to shut down for
this issue, shut the station down and
determine what the problem is. Consult the
Troubleshooting section of this manual for
assistance.
VFD Fault
The VFD sends a fault signal (120 VAC)
directly to the PLC. The display shows,
"Inverter Fault." This is normally a VFD fault.
To determine the nature of the problem, you
must use the VFD keypad display and review
the fault/alarm history. This procedure is
outlined in the VFD section of this manual. A
list of all inverter fault/alarm codes is found in
your VFD manual.
In some instances, the display shows,
"Inverter Relay Fault." In this case the PLC
failed to get a VFD run signal back from the
drive. This could be a problem external to the
VFD. Consult the Troubleshooting section of
this manual for more details.
After a two (2) second time delay, the VFD
pump shuts down. The lag pump(s) continues
to run. The PLC allows three (3) automatic
restarts in a one-hour period. At the fourth
occurrence in a one-hour period, the station
shuts down (hard fault). The red station fault
light on the control panel door comes on, and
the display indicates an "Alarm Shutdown
Alert." Go to "Alarms," and the display should
show either an "Inverter fault" or an "Inverter
Relay fault" has occurred. The fault does not
have to be cleared in order to allow auto
restart.
Once you have determined what the VFD
(inverter) fault is, and have cleared it, press
the station Reset button to clear the alarm
shutdown status.
