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4. Electrical Installation
4.1 Connecting the Main Power:
The VPH-10000-2 requires three phase power. All power connections are made through the heater
control box.
Warning: Electrical shock hazard. Ensure all power is disconnected from the source before
proceeding. Ensure that only qualified personnel are working on this equipment.
a. Turn the single phase power switch off.
b. Turn the three phase disconnect switch to the off position. This will allow access to the heater
control box.
c. Unscrew the four screws on the front of the heater control box.
d. Feed the three phase cable and conduit through the 1" conduit fitting on the left side of the heater
control box. Ensure fitting is air tight.
e. Connect the three phase power into the appropriate terminals (Figure 1a-b). Be sure to tie the
ground wire to the ground block. The three phase power is for the heater, which is a delta wiring
arrangement and thus no neutral wire is needed.
f. Close the heater control box and insert screws.
g. Connect power to main source.
h. Ensure that the manual contactor override switch is in the enable position.
i. Turn the single phase and three phase disconnect switches on.
4.2 Wiring Relays and Alarm Outputs
Warning: Electrical shock hazard. Ensure all power is disconnected from the source before
proceeding. Ensure that only qualified personnel are working on this equipment.
The VPH-10000-2 comes with two pre-wired junction boxes for wiring relays, contacts and 4-20 mA
outputs without having to access the main controller. The junction box labeled “Relay Connections”
contains the terminals for wiring all the relays and alarm contact outputs. The junction box
labeled “Signal Connections” contains the terminals for wiring the 4-20 mA outputs and Modbus
communication. The terminal designations can be seen in Table 1 and Table 2.
