Types Q8WHH and Q8WHM: Electronic on-off relative humidity controllers with IP 65 enclosure


Applications: Relative humidity display or control in cold rooms and commercial applications.

Sensing element: capacitive sensor, protected by plastic housing, with 2 meter cable.

Electronic control features: Miniature intelligent controller (see description P13).

Main advantages:

  • The simplest and most economical electronic controller with digital display.
  • Heavy duty housing for outside use, IP65 and IK10.
  • Simple configuration by user
  • Adjustable temperature differential and selection of heating or cooling action, adjustable humidity differential and selection of humidifying or dehumidifying action
  • If open circuit or missing temperature sensor and if no power supply, output relay will open (Fail safe action)

Standard equipment:

  • Fuse for internal circuit protection
  • Illuminated on-off switch
  • 4 wall mounting removable legs
  • Connection block with 5 terminals for 6 mm² wires and 5 terminals for 2.5 mm² wires. The connection block is equipped with a jumper between terminals 1 and 2, it allows connecting a safety device, a timer, or an external wired remote control.

Cable outputs:

  • Cable gland output board is equipped in standard with two M20 + 1 M24 cable glands (Other cable gland board: 2 x M25)
  • The two back side M20 X 1.5 outputs are equipped with cable glands with silicone gasket to seal the temperature sensor (if this option exists) and the humidity sensor outlet.

Standard Accessories:

  • 10 PA66 red plastic seals, English-French installation manual.
  • Temperature sensor with waterproof PVC probe is included in the control box (if this option exists). Other available temperature sensor, see P15 of this catalogue


  • Infrared remote control
  • Enclosure heater
  • 115-120V power supply.

Power relays: many variations are possible, and are described in the catalogue N°3



Humidity control, remote sensor,
relay output 16A 250V

Humidity and temperature control,
remote sensors, relay output
16A 250V for temperature,
10A 250V for humidity



Wiring diagrams

Humidity control

Humidity and temperature control


2D&3D Drawing