ABB PVS-175 Series, Hardware Manual, Page: 11 / 72

￭ MVS working area safety
The MVS has three working areas:
• AC Cabinet Area
• MV Transformer Area
• MV Switchgear Area
• Free Area
Each work area has separate safety instructions.
Personal protective equipment (PPE)
• Perform any operation on the equipment with suitable work clothes and instruments.
• When choosing a personnel protective equipment, consider environmental conditions
such as humidity, noise, etc. and local regulations.
• Make sure the work clothes and accessories are not prone to generate electrostatic
charges, fires or any other condition that compromises personnel safety.
• The minimum required safety equipment is as follows:
• Safety shoes
• Safety gloves
• Safety glasses
• Head protection
• Hearing protection
• Work clothes
Safety instructions for MV switchgear and MV transformer area
WARNING!
Perform the below instructions before you start working inside the MV switchgear
and/or MV transformer area. Ignoring the instructions can cause physical injury or
death, or damage to the equipment.
1. Identify the MV switchgear and read its safety instructions.
2. Check the operation of the capacitive voltage indicators in all MV switchgear bays (all
phase LEDs are switched on when a voltage is connected).
3. Disconnect the MV switchgear from all possible power supplies (external, auxiliary, and
inverters as well as any parallel connection stations), and secure by locking and tagging.
a. Stop the string inverters outside the MVS. Open the DC disconnecting switches in
each inverter unit and add warning notices. If applicable, open the AC disconnecting
switches in each inverter unit, lock and add warning notices.
b. Open all fuse base switches of the inverter inputs, lock and add warning notices.
c. Open all auxiliary breakers, switches and fuses in the auxiliary service board, lock
and add warning notices.
d. Turn the vacuum circuit breaker of the MV switchgear to open position. Lock and
add warning notice.
e. Turn the disconnecting switch of the MV transformer side of the MV switchgear to
open position. Lock and add a warning notice.
f. Disconnect the MV switchgear from the MV network (all possible external power
supplies, grid and parallel stations). See the User's manual of the MV switchgear.
Lock and add warning notices.
Safety instructions 11