What This Chapter Contains; To Which Drives This Chapter Applies; Description; Applicable Standards - ABB ACS800 Series Hardware Manual

Prevention of Unexpected Start for ACS800-
07/U7/17/37 (+Q950)

What this chapter contains

This chapter describes the Prevention of Unexpected Start function (+Q950). The
chapter deals with wiring, operation and use. An example circuit diagram is included.

To which drives this chapter applies

The chapter applies to the following drives:
Drive type
ACS800-07
ACS800-U7
ACS800-17
ACS800-37

Description

The Prevention of Unexpected Start function disables the control voltage of the
power semiconductors, thus preventing the inverter from generating the AC voltage
required to rotate the motor. By using this function, short-time operations (like
cleaning) and/or maintenance work on non-electrical parts of the machinery can be
performed without switching off the AC power supply to the drive.
The operator activates the Prevention of Unexpected Start function by opening a
switch on a control desk. An indicating lamp on the control desk will light, signalling
that the prevention is active. The switch can be locked out.

Applicable standards

The Prevention of Unexpected Start function complies with the following standards:
• IEC/EN 60204-1:1997 "Safety of machinery – Electrical equipment of machines –
Part 1: General requirements"
• ISO/DIS 14118:2000 "Safety of machinery – Prevention of unexpected start-up"
• EN 1037:1996 "Safety of machinery – Prevention of unexpected start-up"
• EN ISO 12100:2003 "Safety of machinery – Basic concepts, general principles for
design"
Frame sizes Option code and description
R6, R7, R8 +Q950 = Prevention of Unexpected Start
n×R8i
R6i, R7i, n×R8i
Prevention of Unexpected Start for ACS800-07/U7/17/37 (+Q950)
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