Fluid Components International FLT Series - Manual (Page 18)

FLUID COMPONENTS, INTL CHAPTER 2 - INSTALLATION
FLTÔ Series FlexSwitchÔ 2 - 8 Doc. No. 06EN003246 Rev. B
Make sure that the proper relays have been selected for the intended load. See Appendix A for the auxiliary relay
board configuration drawing.
When connecting the relay wiring, do so with complete understanding of what the process requires of the instrument.
The instrument has dual DPDT or single 4PDT relay output contacts dependent on the jumper configuration for each
alarm switch point. For the relay logic, refer to Figure 2-5. Also refer to Table 3-5 and Table 3-6 in
Chapter 3 - Operation. Relay contacts are shown with the relays de-energized. Wire in accordance with the system
requirements.
The control circuit can be ordered with switching voltage outputs without ordering a relay board. This can be used
with customer supplied relays or any other device that has a differential input. The output voltage is 17 Vdc and will
drive a load as low as 1500 ohms. Refer to Figure 2-7 for the output terminals.
Wiring A Remote Control Circuit To An Auxiliary Relay Board
1. Run a four-conductor cable from the control circuit to the auxiliary relay board if the board was not factory
installed. Use the wiring diagram in Figure 2-7 to wire the boards together.
2. Attach the customer wiring as desired using Figure 2-7 as a wiring guide.
Wiring for this configuration is the same as the sensing element wiring to the control circuit on a remote instrument.
Wiring Output Signal Terminals
Two output signals are provided on the control circuit at P1. The signal voltage at positions 1 and 2 represents the
process change. The signal voltage at positions 3 and 4 is proportional to the temperature at the sensing element.
See Figures 2-5 through 2-7. See also Chapter 3 for the physical layout of the control circuit.
Caution: Do not ground terminal 2 of P1. (Terminal 2 is the negative lead of the process signal.) This terminal
is 9 volts above the control circuit ground. The peripheral using this signal must have a differential
input.
These voltages can be used by other peripherals with a minimum load of 100K ohms. The terminal block can be
wired with between gauge 26 and 18 wire (22 gauge wire is normally used). The maximum recommended length of
wire is 1000 feet. Shielding is required on any length of cable. The shield must be terminated at position 4 on P1.
Early versions of the FLT93 require a connecting harness that was supplied with each instrument. The harness can
be ordered if it is missing. The FCI part number is 015664-01. Newer versions of the FLT93 require a supplied
terminal plug.