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MICROgarde controller I and II
04.20.11.18
Relays
Relays are often referred to as Outputs. They internally comprise an armature that flips from
one connection to another. This creates either a closed circuit or an open circuit.
Applying external power (relays do not provide power themselves) via the relay then applies
power from a PSU to other devices, e.g. a lock.
MICROgarde’s two relays are dry-contact changeover type, rated at 30V, 2 A. Connect the
lock to common and either N/C or N/O as described in
Lock supply
.
Devices which have inductive loads (i.e. anything with a coil, such as a secondary relay, bell
or motor) must be fitted with suppression at the device. If in doubt, fit a suppressor. A DC
device can be fitted with a diode (IN4003 or equivalent) as supplied with the MICROgarde.
The suppressor must be fitted at the coiled component terminal (secondary relay, bell,
motor, or lock), and not at the Controller circuit board terminal.
MICROgarde relay connections
MICROgarde connection
Normal use
Alternative use
Connection 11
Relay 1 N/C Normally Closed
Lock Strike Door 1
Spare Relay 1 if Door
1 not defined
Connection 12
Relay 1 Common
Lock Strike Door 1
Spare Relay 1 if Door
1 not defined
Connection 13
Relay 1 N/O Normally Open
Lock Strike Door 1
Spare Relay 1 if Door
1 not defined
Connection 17
Relay 2 N/C Normally Closed
Lock Strike 2 (MG2 only)
Spare Relay 2 if Door
2 not defined
Connection 18
Relay 2 Common
Lock Strike 2 Common
Spare Relay 2 if Door
2 not defined
Connection 19
Relay 2 N/O Normally Open
Lock Strike 2 (MG2 only)
Spare Relay 2 if Door
2 not defined