Product News Release 0018

New Motors for Electric Maxidoors.

12th October 2004

Updated motors have been sourced for Electric Maxidoors.
These new motors have the benefit of:

Both 220V and 380V units have sufficient power to lift our largest door in the price list (20m x 9.1m) even for doors made from 600gsm solid material. Traditionally we have had to limit the maximum size of door with 220V due to lack of motor torque.
All the external control voltages to push-button switches, micro-switches, etc are at 24V, previously it was at 220V. Not only does this improve operator safety but also reduces the cost of electrical installation, as conduit to safeguard against electrocution is not required. This improvement has also resulted in a change in the switchgear configuration.

The contactor box is now fitted at a level adjacent to the motor. This keeps the high voltage cables well above floor level and out of direct contact with personnel. Supplied with the system is 2m of cable between the motor and the contactor box allowing the contactor box to be installed inside, protecting it from the weather

The method of operating the door is via one 24V three push-button switch brought down to floor level. The length of cable between the contactor box and switch = 7m. Additional switches can be supplied upon request.

Technical Specification

	380V Three Phase	220V Single Phase
Power (kW)	1.5	0.75
Current (Amps)	3.2	5.2
Protection	I.P. 54	I.P. 54
Output Speed	24	24
Torque	300	200
Door Operating Speed	11 seconds per meter

Other Improvements

Since 2003 we have been supplying Maxidoors with additional micro switches to improve readability.
The changes are:

Shute-bolt interlock switch for both lower trolleys. These prevent the door being opened when the shute-bolts are engaged to hold the door down on windy days.
Secondary upper limit switches. With the cable randomly rolling on the lifting drum it is sometimes possible for the door to be fully open before the upper limits on the motor engage and switch off the power. If this occurs the Maxidoor may be damaged. The secondary limits are mounted at the top of the tracking and work in series with the main limits to ensure power is switched off when the door is fully open.