2 Engineering
2.10 Switching to the output side
50
DC1 Variable Frequency Drive
04/16 MN04020003Z-EN
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2.10.2 switch-disconnectors
Switch-disconnectors are used as repair and maintenance switches in
industrial, trade, and building service management applications. At the output
of variable frequency drives, they are primarily used to locally switch off
motors (pumps, fans) that pose a risk of unintended starting during
maintenance or repairs. In order to provide greater safety, these switch-
disconnectors can be locked out with the use of padlocks, meaning they
have characteristics comparable to those of main switches as defined in
EN 60204.
Eaton T0…/MSB/…, P1…/MSB/…, and P3…/MSB/… enclosed switch-
disconnectors are designed for local installation with an IP65 degree of
protection. The internal screening plate ensures that screened motor cables
can be easily connected in a way that meets EMC requirements.
The switch-disconnectors on the output side of DC1 variable frequency
drives need to be sized based on utilization category AC-23A
(IEC/EN 60947-3) for the assigned rated motor current and the corresponding
rated operating voltage.
When a motor is being switched off, the DC1 variable frequency drive’s
output (inverter) must be disabled (the FWD/REV enable signal must be
switched off) before the contacts are opened.
For more information and technical data on
T0…/MSB/…, P1…/MSB/…, and P3…/MSB/… switch-
disconnectors, please refer to instruction leaflets
IL008020ZU and IL008037ZU.
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