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7.2
Unpacking
The “eHEnergizer” is typically installed in an explosion proof enclosure allowing its safe usage in areas up
to and including Class I Zone 1.
If the unit has been shipped with the recommended explosion proof enclosure it is necessary to remove
the cover from the enclosure to expose the field wiring terminals.
Extra care must be taken when handling the sealing o-ring at the base of the enclosure so as not to
pinch it.
Figure 2 - Explosion Proof Cover Removal
7.3
Field Wiring
When the explosion proof enclosure is used, field wiring must be passed through the ¾” Female NPT
connection point on the base of the enclosure. For use in hazardous areas a seal fitting (EYS or similar)
must be provided within 18” of the enclosure connection point. With a proper seal, the assembly is
suitable for Class I Div 1/Zone 1 installation.
Signals from a BMS control unit (PLC) to the “eHEnergizer” travelling more than 1000ft should have
wiring selected that minimizes voltage drop to 10% at rated current.
7.3.1.1
Schematics
Consuming maximum 2A of power it the PHE-24 unit may be powered direct from a BMS control unit (e.g.
PLC). Otherwise interposing relays are required. Similarly, the PHE-120 unit can be wired as per traditional
ignition transformers or via an interposing relay to the PLC. The wiring schemes are illustrated below
(Figure 3).
Sealing O-Ring
