Technical Manual
Page 14
This input must be activated to enable remote
load. Use a wire link (3*) or a local/remote
switch (3**, not supplied).
The remote load input logic of some
electronic controllers is reversed; the
compressor will ‘load’ when the input is open
circuit and ‘unload’ when closed circuit.
Use the ‘normally closed’ output contact (pin
5*) of the ‘mi-PCB’ in this instance.
4.7.2
2-Wire Pressure Switch:
For an air compressor fitted with a 2-wire
electro-mechanical pressure switch, connect
the ‘mi-PCB’ output contacts in series with the
pressure switch. This will leave the pressure
switch ‘in-circuit’ allowing the pressure switch
to perform the function of excess pressure
protection.
Ensure the pressure settings of the original
pressure switch are adjusted at least 0.5bar
(7psi) higher than the operating pressure
settings of the Metacentre DCO. Pressure
switch settings near, or below, the Metacentre
DCO pressure settings will disrupt successful
pressure control.
4.7.3
3-Wire Pressure Switch:
For an air compressor fitted with a 3-wire
electro-mechanical pressure switch, connect
the ‘mi-PCB’ output contacts as illustrated.
This arrangement will leave the pressure
switch ‘in-circuit’ allowing the pressure switch
to perform the function of excess pressure
protection.
Some older compressor pressure switches
operate in reverse; the solenoid (unloader) is
connected to the normally closed pressure
switch terminals. In this instance ensure the
‘mi-PCB’ common pin 4 is connected to the
normally closed pressure switch output
terminal, and reverse the connections to pins 5
and 6 of the ‘mi-PCB’.
Ensure the pressure settings of the original
pressure switch are adjusted at least 0.5bar
(7psi) higher than the operating pressure
settings of the Metacentre DCO. Pressure
switch settings near, or below, the Metacentre
DCO pressure settings will disrupt successful
pressure control.
*
4
5
6
4
5
6
4
5
6
4
5
6
