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CHAPTER 4. ELECTRICAL INSTALLATION
GUIDELINES
The VRF™ unit is a line powered point level switch with a DPDT isolated relay contact output. Wiring
will consist of:
Grounding
Input supply line power
Output relay contacts for signal/control
CONDUIT-CABLE CONNECTION
Two threaded 0.75 in. NPT female conduit openings are provided in the housing for input and output
wiring. When only one conduit opening is used for installation, the unused opening must be sealed
with a suitable Type 4X/IP66 0.75 in. - 14 NPT plug with pipe sealant in order to maintain approval
requirements.
INPUT POWER
The VRF™ unit is either an AC or DC input model. Consult the model codes in Chapter 1 and the
nameplate of the unit to determine the proper power supply.
CONNECTION INFORMATION
See Figures 4.1 and 4.2 for location of input and output wiring.
WARNING!
Either AC or DC power is to be connected to the power input depending on the model. Consult the
nameplate of the unit and Chapter 1 to determine what type of power is required. Consult Chapter 1 for
the allowable voltage ranges.
CONNECTION INFORMATION/WIRING DIAGRAM
See Figure 4.1 for location of input and output terminal blocks. Agency approved insulated barrel type
terminals are supplied in the input terminal block to provide additional safety. These terminals must be
used in order to maintain approval requirements. See Figure 4.2 for output contact positions during
stages of operation.
WARNING!
An electrical earth ground connection must be made to the housing input ground screw located inside
the enclosure. See Figure 4.1 for location. This connection is needed for both electrical safety and
proper operation of the unit. This is required for both AC and DC units.
WARNING!
The external ground wire (included) MUST be attached to the wall or the top of the metal vessel in order
to provide the proper reference to the probe.
