The Hekatron THM447 is a Wall Mounted Electromagnetic Door Retainer. The THM 447 is used to keep self-closing doorways, such as fire doors, smoke doors and other doors or gates open. The THM-447 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 THM447 comes with a hermetically sealed terminal box and a PG cable gland. The pole face and the anchor plates are galvanically nickelplated. This makes the THM447 suitable for harsh conditions, up to IP65. The THM 447 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.
The THM447 Door Holder Magnet is equipped with a hall sensor which monitors the magnetic flux and signals whether the door is retained by the magnet via an additional output (open collector). This signal can be forwarded to a superior station.
