Intek RheoVac SENTRY User Manual

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2.5 ELECTRICAL CONNECTIONS (Make all hardware & plug-in connections with power off)

A. Distribution Box

1. Contents

a. Connection point for the RS485 wires (Blue and White), +24vdc power (Red), ground

(Black), and shield.

b. Connection point for the input from and output to other distribution enclosures.
c. Connection points for up to four devices (probes or transmitters).
d. Power "on" LED.

2. Connections

a. Mount the probe distribution enclosure(s) centrally among the devices for which it is

supplying power and communications.

b. Install ¾” liquid-tight flexible conduit between the distribution enclosure and the

probes unless ¾ rigid conduit is used for long distance runs.

c. The probe connector has an adapter, which allows the attachment of the ¾" flexible

conduit connector.

d. Connect the probes to the distribution enclosure using the manufacturer supplied four

conductor shielded cable. Probe cable connections are shown in Figure 5.

e. A termination resistor is required in the last distribution box (farthest point out from

CPU). This resistor is accessed via a jumper at JP7 in the last distribution box. The
jumper should be set on "EN” on JP7 to enable that resistor.




Inspect and VERIFY these connections carefully. Improper connection

could damage the RS485 IC in the probe assembly as well as the other probes.