ENMET EN Series - Manual (Page 5)

Sensor/Transmitter, Toxic Gas & Oxygen ENMET Corporation
3
2.1 Installation of Sensor/Transmitter
1. ❏ Remove the cover, and mount the S/T in a location appropriate for the application. Use the enclosure mounting holes as
shown in Figure 2. The sensor faces down. Pay particular attention to the source and density of the target gas in choosing
the S/T location.
2. ❏ The hole in the left side wall of the S/T enclosure is sized to accommodate a liquid tight conduit fitting. Run conduit from
the S/T to the control. If intrinsically safe barriers are supplied, because the S/Ts are in a classified location, follow the
applicable electrical code provisions for intrinsically safe wiring. Run two wires through conduit. If the conduit is
metallic and does not contain other wiring likely to generate interference signals, unshielded insulated wires can be used.
Otherwise, use two wire shielded cable and ground the shield to the S/T enclosure. The S/T enclosure should be grounded
to earth ground for maximum RFI protection.
3. ❏ Connect the plus wire to TB1-1 and the minus wire to TB1-2 on the S/T circuit board, as shown in Figure 2.
C AUTION : Before connecting S/T to C ONTROL remove the power source to C ONTROL . Failure to do so may cause damage to
sensitive components.
Figure 2: Sensor/Transmitter 4 – 20mA in NEMA-4 Package, Internal View
Figure 2a: Sensor/Transmitter 4 – 20mA in NEMA-4 Package, Internal View
4 – 20mA,
12 – 28VDC
Mounting Hole
2 places
Liquid Tight
Conduit
Fitting
TB1
Red LED
Sensor
Circuit Board
POTs: Gain and Zero
• Note: No Zero pot in oxygen S/T
Test Points
NEMA-4 Aluminum Enclosure
• shown without cover
4 – 20mA,
12 – 28VDC
Mounting Hole
2 places
Liquid Tight
Conduit
Fitting
TB1
Red LED
Sensor
Circuit Board
POTs: Gain and Zero
• Note: No Zero pot in oxygen S/T
Test Points
NEMA-4 Aluminum Enclosure
• shown without cover