2.6 Connections and settings
All connections described are with reference to the terminal block mounted within IRmax
connector main body. The terminals on the IRmax connector PCB are marked '+', 'sig'
and '0 V'. Correct polarity should be observed when connecting the IRmax to control
equipment.
IRmax is factory set as a 'current sink' device unless otherwise specified when ordering. To
reset to 'current source', remove the back nut and move the two links on the terminal PCB
from the 'sink position to the 'source' position, as shown in Diagram 7.
Note: The external grounding terminal is only to be used where local authorities
permit or require such a connection. Where possible, to limit radio frequency
interference, the auxiliary junction box and cable armour should be grounded at
the control panel (safe area) only to avoid earth loops.
1
2
3
Wiring
Number Colour Function
1
2
3
PC communications
kit connector
Diagram 7: Sink/source jumper location
The 4-20mA signal can be set to current 'Sink' or 'Source' using the pins and jumper link
shown in Diagram 7. Set to current 'Sink' by fitting the jumper link to pins 3 and 4 as
shown on the left-hand photograph. Set to current 'Source' by fitting the jumper link to
pins 1 and 2 as shown on the right-hand photograph. IRmax will be set to current 'Sink'
unless specified otherwise when ordering.
LED indication: an LED is fitted to the terminal PCB to indicate the current
operating status. Refer to Section 6 on page 17 for more information.
Detecting Gas Saving Lives
+V
0V
CONTROLLER
Sg
EARTH
Red
+V
Black 0V
Green Signal
IR Display
connector
Status LED
11
2. Installation
Sink
setting
Jumper
settings
Source
setting