The MSU series of pushbutton control units has been designed to match MEM's ADS8 motor starter range. Simplicity, versatility and robust construction have been successfully allied to attractive styling.

One, two and three button types are available in a variety of configurations. 3-button types 23MSU and 23MSU/L are supplied with a fitted front label reading FORWARD, REVERSE, STOP.

21MSUML emergency stop units conform to clause 6.2.3 of BS 4163 - Workshop emergency stop systems (schools and similar establishments).

Contact Blocks
Each contact block comprises 1 - N/O and 1 - N/C contact.

Operation
Start units are push to make (N/O).

Stop units are push to break (N/C). The latching device where fitted holds the stop pushbutton in the depressed position until the latch is released by clockwise rotation of the mushroom head.

Performance Rating
MSU pushbuttons comply with:- BS EN 60947-5-1: 1992, IEC 60947-5-1: 1990. 6A, 415V AC. Utilisation category AC-15. One 'a' contact + one 'b' contact per way. Form Za Uimp =6kV.
STOP, latching pattern units comply with BS EN 60947-5-5: 1998, IEC 60947-5-5: 1998.

Enclosures
Covers are tough polycarbonate while bases are glass-filled polycarbonate. Standard protection is IP65. The enclosure material is resistant to diluted mineral and organic acids. 20mm conduit knockouts complete with M20 conduit threads are incorporated at top and bottom. Single way enclosures may be turned through 90° to permit side cable entry.

Flame resistance to UL94:VO.

Ambient temperature rating -5°C to +40°C.

Terminal Cable Capacities
Switch and earth terminals 2 x 1mm² - 2.5mm² rigid, 2 x 1.5mm² - 2.5mm² flexible.

Single way control stations are also readily available with a range of 22mm cover mounted control and indicating devices. In addition to those listed other 22mm devices may be supplied to special order.