The alarm relay will only close if a very low pressure is detected.
This will make the alarm relay contacts open and close every second during
learning mode. This can be used to operate a light so the operator knows the
switch is in its learning mode.
The alarm relay will only close if the ramp up timer times out. This can warn
the operator he has failed to instigate the learning phase in the allotted
time.
The alarm relay will only close if the pressure rises above the very high
pressure setting. There is no time delay on this setting.
This will only close the alarm relay if the controller has been unable to lock in
a set point because the pressure has not stabilised.
This allows for control of auxillary equipment such as stirrers, priming valves
and any other device that it is useful to run with, or prior to the pump
starting.
Once selected, it closes the alarm relay contacts either as soon as the
prestart delay starts, or if the prestart delay is not selected it will close
the contacts while the pump is running. If a time is selected it will run for
that period then open the alarm relay contacts. If no time is selected it
will hold the relay contacts closed during the prestart delay and
continues to hold them closed until the pump shuts down in normal
operation or due to a fault. e.g. start a stirrer before the pump but
continue to run the stirrer while the pump is running.
Alarm relay timer
Indicate use of remote input
Closed if ramp up timer times out
Closed on very low pressure fault
Closed on very high pressure fault
Closed if reference pressure is not stable
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