ZENITH 140
INSTRUCTION MANUAL
102
Consider the example of an application using 2 pumps. Each pump is
connected and controlled by one of the Zenith relay outputs, the pump duty
and setpoints have been programmed as detailed in
Using the Relays
,
earlier in this chapter. The signals providing
details on the “lead” or “duty”
pump ‘status’ are connected to the digital inputs as described in
Chapter 2
Installation
, and the input
Type
P372, 375, 378, 381, 384, 387, 390 is
configured as detailed in
Input Type
, earlier in this chapter.
Pump 1
is connected and programmed to operate on
Relay 1
Pump 2
is connected and programmed to operate on
Relay 2
Duty Input 1
signal is connected to
Digital Input 3
Duty Input 2
signal is connected to
Digital Input 4
When no signals are present on either Digital Input 3 or Digital Input 4 then
devices will run in the “
auto
” mode, as determined by the Zenith, in
accordance with its programmed settings. If a signal is seen on Digital Input
3,
duty
selected for
Pump 1
, then the pump connected to Relay 1 will
assume the role of “lead”/duty” pump, regardless of the settings
programmed in the Zenith. When the level rises to the
ON Setpoint
, for the
first
pump, relay 1 will energise and Pump 1 will ‘start’, in the normal
manner. If the level continues to rise, then relay 2 will energise and Pump 2
will start in accordance with the settings programmed for pump 2.
If a signal is seen on Digital Input 4,
duty
selected for
Pump 2
, then the
pump connected to Relay 2 will assume the role of “lead”/duty” pump,
regardless of the settings programmed in the Zenith. When the level rises to
the
ON Setpoint
, for the
first
pump, the relay 2 will energise and Pump 2
will ‘start’, in the normal manner. If the level continues to rise, then relay 1
will energise and Pump 1 will start in accordance with the settings
programmed for pump 2.