User manual

Model: 2100 &2300 Series
2100UM22.DOC Rev: 2.2
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Since the pump should be turned off if the Arjay unit fails or in the event of a power failure i.e. the
positive action state is not the same as the failure state, the failsafe setting should be No.
Since the positive action is desired when the level drops below the low control point, the relay
setting should be Low Acting.
Since the pump starter requires power to turn on the pump, the normally open contacts should be
used.
As per example 1, the time delay is optional to turn on the pump.
3- An alarm buzzer and light must be turned on if the level in a tank exceeds 97% or in the
event of an instrument or power failure.
Settings:
High control point: 97%
Low control point: 97%
Failsafe: Yes
Relay action: High acting
Contacts used: Normally Closed
Explanation:
In this case the positive action is turning on a buzzer and light.
Since the buzzer / light should also be turned on if the Arjay unit fails or in the event of a power
failure i.e. the positive action state is the same as the failure state, the failsafe setting should be
Yes.
Since the positive action is desired when the level rises above the high control point, the relay
setting should be High Acting.
Since the buzzer / light require power to turn on, and the failsafe setting is Yes, the normally
closed contacts should be used.
The High and Low control points are set to be identical. The low point can be set a little lower i.e.
95% to provide some dead band.
In an alarm application, the alarm time delay should be set as low as possible.