PULSAR MEASUREMENT
99
Device Fail
The digital inputs are used to indicate a ‘fail’ situation which effect devices,
which are connected to the relay outputs of the Zenith, e.g. failure of a
pump, screen, valve, etc. This information is then used to initiate changes to
the Zeniths control regime to meet the demands of the situation.
Let us consider the example of an application using 2 pumps, each pump
has the capability to provide a signal indicating its ‘run’ status. Each pump is
connected and controlled by one of the Zenith relay outputs, the duty and
setpoints have been programmed as detailed in
Using the Relays
, earlier in
this chapter. The signals providing details on the pumps ‘run 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
Pump 1 Fail
signal is connected to
Digital Input 1
Pump 2 Fail
signal is connected to
Digital Input 2
Each digital
input
must be assigned to the device relay output that it relates
to, this is determined by
Assignment P374, 377, 380, 383, 386, 389, 392.
In the case of our example
Digital Input 1
will be assigned to
Relay 1 (P374
= 1)
and
Digital Input 2
will be assigned to
Relay 2 (P377 = 2)
.
When the level rises to the ON Setpoint of Relay 1, the relay will energise,
and Pump 1 will ‘start’, in the normal manner. If the pump starts and
correctly runs and
no change of ‘run’ status will b
e seen on the digital input
and the pump(s) will be allowed to operate as programmed.
Should a pump
fail
, a change of ‘run’ status would be seen and a
Device
Fail,
condition would be detected on the corresponding digital input, this
will result in the rel
ay for the ‘failed’ pump being de
-energised, and the
pump being switched OFF. The setpoints of the ‘failed’ pump will then be
passed to the second pump, which will take over to complete the pumping
operation.
Содержание Zenith 140
Страница 1: ...Zenith 140 Instruction Manual ...
Страница 2: ...2 ...
Страница 14: ...ZENITH 140 INSTRUCTION MANUAL 14 EU Certificate of Conformity ...
Страница 17: ...PULSAR MEASUREMENT 17 Dimensions Fascia Mount The dimensions of the wall fixing holes are as shown below ...
Страница 19: ...PULSAR MEASUREMENT 19 Terminal connection details Fascia Mount The terminal details are as illustrated below ...
Страница 160: ...ZENITH 140 INSTRUCTION MANUAL 160 NOTES ...