Metacentre DCO
Page 13
For a compressor that has no available or
accessible Alarm circuit it is recommended the
additional relay (2) be connected to a part of
the circuit that is de-energised when the
Emergency Stop is activated (1).
2
1
3
8 7
For a compressor equipped with a ‘volt-free’
Alarm contact (3), connect ‘mi-PCB’ terminals
7 and 8 to the Alarm contacts in series with the
main motor Line (or Delta) auxiliary contact.
The Alarm contacts must be ‘closed circuit’
when no Alarm condition is present and the
compressor is ready and available to
automatically respond to a load command.
2
1
3
8 7
If the main motor Line (or Delta) contactor is
not equipped with a spare ‘volt-free’ auxiliary
contact a relay (2) can be installed in parallel
with the contactor.
4.7 Load Control Output
The ‘mi-PCB’ is equipped with a load control
relay, the contacts of which can be used to
regulate the compressor in accordance with
Metacentre DCO pressure control.
Ensure the compressor is equipped with
independent excess pressure protection.
The ‘mi-PCB’ connection examples shown
in this manual are intended as guideline
only. The majority of compressor control
circuits will closely resemble one of the
diagrams – examine the compressor
control circuit diagram. Some compressors
have variations in arrangement, operation
and/or function; consult your compressor
supplier/specialist for advice if necessary.
Lethal voltages may be present on the
terminals of an air compressor pressure
switch. Isolate the air compressor power
supply before starting any work.
4.7.1
Remote Load Digital Input:
For a compressor controller equipped with a
remote load digital input (1), use the ‘mi-PCB’
switching contacts to active the load input.
Some compressor controllers may also be
equipped with a ‘remote load enable’ or
‘remote/local’ input (2).
6
5
4
240V '
CE
'
115V '
UL
'
4A
NO
C
NC
4 5 6
4 5 6
mi-PCB
4
5
6
1
2
**
*
3
