NDD Series - NO2 Transmitter
Installation Manual
Feb 2, 2016
NDD-INS-002
Page 2
Wiring
Use 22 AWG shielded wire for all connections and do not locate the device wires in the same conduit with wiring used to
supply inductive loads such as motors. Disconnect the power supply before making any connections to prevent electrical
shock or equipment damage. Make all connections in accordance with national and local codes.
The product is a 3-wire sourcing. Follow the example wiring diagrams to determine the correct wiring for the product. All
models have the same terminal functions.
Connect either an AC or DC power supply to
POWER
and
COMMON
and the 4-20 mA signal is available on the
OUTPUT
terminal with respect to
COMMON
. The current output operates in the Active mode and does not require a loop
power supply. This means
the signal current is generated by the transmitter and must not be connected to a powered
input or device damage will result.
This is the typical operating mode of a “three-wire device”. Check the controller Analog
Input to determine the proper connection before applying power.
Ensure the controller Analog Input (AI) matches the transmitter output signal type before power is applied. The current signal
has a maximum load that it will drive. Follow the ratings in the Specification section or inaccurate readings may result.
The relay output is available on the
NO, NC
and
R.COM
terminals. The relay R.COM terminal is NOT connected to the
signal or power supply COMMON terminal. The relay output is completely isolated and has both Normally Open (NO) and
Normally Closed (NC) signals. These signals can be used to directly control alarms, ventilation fans or may be connected to
digital inputs of the B.A.S. for status monitoring.
