4.5 RTD Input (2, 3, or 4 wire)
48/96 VTR: 3-wire RTDs are most common and are wired to 8, 9, and 10 on the 96VFL and
terminals 7, 8, and 9 on the 48VFL as shown in the diagrams above.
96VFL: For 2-wire RTD, connect across terminals 8 and 9 and jump 9 to 10. For 4-wire RTD
connect the resistance across 8 and 9 and connect the remaining two wires to 8 and 10.
48VFL: For 2-wire RTD, connect across terminals 8 and 9 and jump 7 to 8. For 4-wire RTD
connect the resistance across 8 and 9 and connect the remaining two wires to 7 and 9.
4.6 Control Relay Wiring
A basic VFL controller includes one control relay (OUT 1), the second control output (OUT 2)
is optional.
Control relay outputs are single-pole, single-throw (normally open N.O.) mechanical
switches. When the controller activates a control relay, the normally open switch closes. The
relay itself does not provide power. AC or DC power must be wired in series with the relay
and control device as shown below. Relays are rated 5 Amps @ 110V AC or 24VDC (Resistive
Loads).
In the diagram below terminals ‘x’ and ‘y’ represent the VFL rear terminal designations, see
the table below for the specific terminal numbers.
FIGURE 4.2: NORMALLY OPEN (N.O.) CONTROL OUTPUT WIRING
4.7 Pulsed DC Trigger Output Wiring
The DC Trigger output delivers 24V DC (approx.) across the same terminals that are used for
the relay outputs. See Control Relay terminals table above.