description
The RHT-WM Relative Humidity and Temperature Transmitter converts these two physical parameters into two industry standard, isolated, highly stable and interference free 4 to 20 milliamp signals. The sensors are mounted on a probe tip and are protected by a filter cover. Both outputs are two wire transmitter loops, requiring a 24Vdc (nominal) supply in both loops. The same pair of wires that supply power to the circuitry then carry the signal to the measuring device. The two outputs would normally be used as inputs to PLCs, controllers, digital indicators, or SCADA or telemetry systems.
specification
- Power supply: 12 to 30 Vdc
- Range: temperature from 0 to 100°C, RH from 0 to 100% non-condensing (default - see below for options)
- Output: Dual isolated 4-20mA signals (reverse polarity protected)
- Accuracy:
- ±1.5% RH @ 25°C (from 20 to 80% RH)
- ±0.5°C @ 25°C (max ±2°C from -40 to 80°C)
- Maximum hysteresis ±1% RH
- Repeatability: ±0.5% RH typical, ±0.1°C temperature
- Response time: less than 10 seconds
- Working temperature: -10 to +65°C, 0 to 95% RH
- Enclosure: wall-mounting grey ABS
- Cable entry: single PG7 gland
- Dimensions: 58x68x35mm excluding gland and sensor (35mm)
Connections
Note that each independent transmitter (RH and temperature) needs only a two-wire connection to a power source (12Vdc to 30Vdc). The 4-20mA measuring signal flows through the same two wires taking the signal to the measuring device. The power cable passes through the cable gland and is attached to the screw connector according to the instructions on the inner side of the box cover. The maximum LOAD resistance plus the wires resistance can be calculated as: LOAD = (Vdc -12)/0.02 ohms (where Vdc is the voltage of the power supply).
Re-Ranging
The RHT-WM is supplied ranged 0 to 100% and 0 to 100°C as default. If you require any other range we can reprogramme this for a £5 fee (select option below) - or alternatively you may wish to invest in the
TxConfig adaptor and Windows software, which will allow you to totally configure and re-configure the instrument yourself.
options The RHT-WM is also available with an output range of 0 - 10Vdc. Use the buttons above to select if required. Options coloured
green are available ex-stock and can be despatched immediately.
associated productsClick here to add a Sintered Bronze Filter to your order.Click here to add a Teflon (PE) Sintered Filter for RHT Transmitters to your order. downloads 
