2 Engineering
2.10 Switching to the output side
50 DC1 Variable Frequency Drive 04/16 MN04020003Z-EN www.eaton.com
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.