The Hekatron THM 441 is a Wall Mounted Electromagnetic Door Retainer. The THM 441 is used to keep self-closing doorways, such as fire doors, smoke doors and other doors or gates open. The THM-441 must be connected to a smoke detection system, which will break the circuit to de-energize the electromagnet, if a fire occurs. This will allow the door to close, and stop the fire from spreading.
The Hekatron THM441 comes with a built-in heating system, making it suitable for extremely low temperatures in the -40 °C to +20 °C range, and it is therefore used in cold stores (refrigerated and deep-frozen products). An enclosure design featuring a PG cable gland ensure a IP65 rating.
The THM 441 is provided with a spark-suppression diode (free-wheeling diode) to protect the contacts against premature erosion and voltage surges, plus a reverse polarity protection diode.
