MN301535 Rev A
17
|
Appendix
Step Eight
RELAY LOGIC – AUTOMATIC FILLING AND EMPTYING
Latching relay will only switch when both level switches are in the same state.
One Switch Dry, One Wet
Both Switches Wet
Both Switches Dry
In this state, the relay will never
switch, regardless if this is an Auto
Fill or Auto Empty application.
In this state, the relay will typically
energize for an Auto Empty
application and will typically de-
energize for an Auto Fill
application.
In this state, the relay will typically
energize for an Auto Fill application
and will typically de-energize for an
Auto Empty application.
Note:
The state of the application (either filling or emptying) can never be confirmed when one switch is Wet
and the other is Dry. Only when both switches are in the same state (both Wet or both Dry) can confirmation
of the relay status (energized or de-energized) occur.
RELAY LOGIC – INDIEPENDENT RELAY
Relay will act directly based upon the status of the level switch. When the level switch is Wet, the input LED
will be ON (Amber). When the level switch is Dry, the input LED will be Off.
Single Switch Wet
Single Switch Dry
In this state, the relay can be energized with
Invert in the OFF setting or can be de-energized
with Invert in the ON setting.
In this state, the relay can be energized with
Invert in the ON setting or can be de-energized
with Invert in the OFF setting.
Note:
Always check the status of the level switch and compare that status against the Input LED. If the level
switch state (Wet or Dry) corresponds to the Input LED, proceed to the relay. If the level switch state (Wet or
Dry) does not correspond to the input LED, then check the functionality of the level switch.