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HF3 Series Temperature & Humidity Transmitters

HF3 Series Temperature & Humidity Transmitters

Quick Overview

The new Hygroflex 3 Series is the latest development in HVAC transmitters for relative humidity, temperature and dew point. The HF3 series offers you maximum reproducibility and a guaranteed system accuracy of <2% RH and 0.3 K. The transmitter has 2 or 2x2 wire 4 - 20mA loop outputs or 3 wire 4-20mA/0-10V outputs (User scaleable with software). The transmitters come in various configurations and the optional HW4 Software allows many useful functions to be activated.
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The HygroFlex 3 series is ideal for cost sensitive applications where the exact measurement of humidity and temperature is still required. The transmitters can be used in a variety of fields for heating, ventilation and air conditioning applications, greenhouses, museums, warehouses, libraries, railways stations and for climate control in office buildings.


Device Type

HF32 2-wire; HF33 3/4-wires

Integrated sensors


Humidity sensor

ROTRONIC Hygromer® IN-1

Temperature sensor

Pt100 1/3 Class B

Accuracy at 23 ±5 °C

±2.0 %rh / 0.3 K (±1.0 %rh / 0.2 K Type R)

Resolution AirChip3000

<0.02 %rh / 0.01 K

Long-term stability humidity sensor

<1 %rh / year

Response time τ 63

<10 s

Measurement range

-40…60°C / 0-100 %rh

Electronics operating range

-40…60°C / 0-100 %rh (-10…60°C with LCD)

Display (Space version only)

Graphic LCD (HF32S: no backlight) Parameters freely configurable.

Alarm functions (programmable)

Open or shorted sensor

Output signals

Freely scalable by user 0-1V, 0-5V, 0-10V, 0-20 mA & 4-20 mA

Change in signal type

HF33 only

Power supply

HF32: 10...28 VDC: 10 V + (0.02 x load)  HF33: 15…40 VDC/12…28 VAC

Power consumption

HF32: max 40 mA, other models < 100 mA

Circuit type

HF32: 2 x 2 wires, HF33: 3/4 wires

Min. / Max. load

V-signal:≥1 kΩ/V / mA signal: ≤ 500 Ω

Firmware update

Via service connector, requires HW4 software

Sensor diagnostics (Drift, state)

Programmable.Default:            off

Sensor protection

Polyethylene filter

Max. air velocity

20m/s at probe


Via ROTRONIC accessories Humidity: multi point; temperature: 2 points

Hygro- /Thermostat

2 Relays, HF34 only

Data logging 

Internal, 2000 data point memory

Dewpoint /frostpoint calculation


PC interface (service connector)

With ROTRONIC interface cable, HW4 compatible          

Housing material / weight

ABS / approx. 120g

Cable connections

1 x M16x1.5, on terminals


CE- compliant, 2007/108/EG

Audit trail, Electronic Records

FDA CFR21 Part 11 and GAMP compliant

Availability: In stock

Price range : £216.00 - £440.00

Price as configured: £216.00

* Required Fields

Price as configured: £216.00


Part Builder

Description       HF3 Transmitter Series. Humidity Range 0-100%, Temperature Range is customer specific.

Components / Downloads

For further information, technical advice, or a quotation please call or email us. If you are not sure which product you need one of our technical sales advisors will be happy to discuss your application. We also accept company purchase orders by fax or post. Credit card orders can also be placed over the phone for any product.

HF3 Series Transmitter
HF3 Series Transmitter.
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