21
Operation, alarm and testing
Level controller NRR 2-50 Displays
Operation
Action
Display
Function
Actual value = setpoint
MIN and MAX LEDs do not
light up
MIN output contacts 16/18 open,
17/18 closed.
MAX output contacts 21/23 open,
22/23 closed.
MIN alarm
Switchpoint for MIN water level
reached or exceeded.
MIN LED flashes red
De-energizing delay in progress.
MIN LED lights up red
Delay time elapsed, MIN output contacts 16/18
closed, 17/18 open.
MAX alarm
Switchpoint for MAX water
level reached or exceeded.
MAX LED flashes red
De-energizing delay in progress.
MAX LED lights up red
Delay time elapsed, MAX output contacts 21/23
closed, 22/23 open.
Operation
Action
Display
Function
Actual value = setpoint
Valve and MIN/ MAX LEDs do
not light up
Valve output contact 16/17/19 open.
MIN output contacts 16/18 open,
17/18 closed.
MAX output contacts 21/23 open,
22/23 closed.
Value above or below setpoint
Value above or below setpoint.
Valve OPEN LED flashes amber Control valve opens, valve output contact
16/19 closed.
or
Valve OPEN CLOSED flashes
amber
Control valve opens, valve output contact 17/19
closed.
MAX alarm
Switchpoint for MAX water
level reached or exceeded.
MAX LED flashes red
De-energizing delay in progress.
MAX LED lights up red
De-energizing delay elapsed, output contacts
21/23 closed, 22/23 open.
or
MIN alarm
Switchpoint for MIN water level
reached or exceeded.
MIN LED flashes red
De-energizing delay in progress.
MIN LED lights up red
De-energizing delay elapsed, output contacts
21/23 closed, 22/23 open.
Level controller NRR 2-51 Displays
continued
