Atex-Certified Motor Thermal Protection Function With Ptc Thermistor Relays; (+L513+Q971); Contents Of This Chapter; Option Description - ABB ACS880 Series User Manual

ATEX-certified motor thermal protection function with PTC thermistor relays (+L513+Q971) 17
ATEX-certified motor thermal protection
function with PTC thermistor relays

(+L513+Q971)

Contents of this chapter

This chapter describes the ATEX-certified motor thermal protection function (option
+L513+Q971) and gives instructions on how to wire, install and start up the function. It also
describes the PTC thermistor relays available for the option and gives fault tracing and
maintenance instructions. The safety data is also given.

Option description

This protection function monitors the temperature of a motor with PTC resistor sensors (PTC
thermistors) in a potentially explosive atmosphere. The function is activated when the PTC
sensor resistance exceeds the overtemperature limit. It is possible to:
• monitor the motor bearings or stator windings (+L513+Q971)
• monitor the motor bearings and stator windings (+2L513+Q971 or +3L513+Q971).
The safety function described in this manual activates the Safe torque off (STO) function of
the drive when it detects motor overtemperature. The STO function of the ACS880 drives
is certified (SIL 3 according to EN/IEC 61800-5-2 and IEC 61508). When activated, the STO
function disables the control voltage of the power semiconductors of the drive output stage.
This prevents the inverter from generating the torque required to rotate the motor. The motor
coasts to a stop. For a detailed description of the STO function, see the hardware manual
of your drive/inverter unit.
ACS880-07/17/37 and ACS880-17LC/37LC drives with option +Q978: Also the main
contactor/breaker is opened.
3