Alarm connections
The DPA has a high inbuilt immunity to noise spikes caused by
switching inductive loads like solenoids or relay coils. However, it
is important to use suppression capacitors across inductive loads
to preserve the relay contacts and to reduce the effect of switching
spikes on nearby circuits.
The alarm outputs are dual SPDT relay contacts with built in
suppression capacitors fitted across the normally open and common
contacts.
DPA/DMA
1 2
Input connection diagrams for mA current inputs.
16
DPA/DMA
2
4
Twisted pair cable
Twisted pair cable
Ground cable shield at signal source only
Ground cable shield at transmitter end only
DC mA
source
–
+
2-wire
Transmitter
–
+