RH-T Datasheet, PDF (4/8 Pages) Amphenol Corporation – Space, Duct, and Outside Air Configurations

RH/RHT Series Wiring
Wiring Guidelines
Outputs: Relative Humidity
Output: Temperature (Optional)
4·20 mA Current Output
The 4-20 mA transmitters will provide a linear
proportional signal with 4 mA corresponding to 0%
RH and 20 mA to 100% RH. These are loop powered
devices; therefore, only two wires are required.
0-5 Volt Voltage Output
The 0 to 5 volt transmitters provide a linear proportional
output at terminal “O” with 0 volts equivalent to 0% RH
and 5 volts to 100% RH.
The voltage output transmitters can be wired as a
three wire transmitter or as a four wire transmitter to
eliminate the effects of wire length. The output voltage
is with respect to Terminals “N” (power supply return)
and/or “G” (signal ground) which are common at the
transmitter.
The temperature option (if ordered) is a separate circuit
board but mounted in the same housing along with the
relative humidity transmitter.
The 4·20 mA transmitters output is linear and
proportional to the range specified when the
transmitter was ordered. The low range temperature
(4 mA) is marked on the ZERO pot and the high range
temperature (20 mA) is marked on the SPAN pot.
Standard range is - 20° to 140°F (this range is supplied
when no range is specified at time of ordering).
The temperature transmitters are entirely separate
circuits from the RH transmitters. Transmitters are
loop powered devices. Therefore, only two wires are
required. One wire may be common with the RH
transmitter.
Wiring
Wiring for the transmitter should be twisted pair(s)
16·22 AWG approximately 2 turns per inch. In
installations near electric motors or sensitive electronic
equipment, use shielded cable. Wiring should be run
through conduit using the 1/2” EMT compression fitting
supplied on the unit.
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