Can we use Easergy P3F30 to carry out Undervoltage protection function (ANSI 27) on two busbar sections (with two different sets of voltage transformers) ?

Issue:
Customer will use Easergy P3F30 on Buscoupler cubicle and want to protect against Undervoltage (ANSI 27) on both busbar sections.

Environment:
Easergy P3 protection function

Resolution:
For Easergy P3F30 to protect against Undervoltage (ANSI 27) on two busbar sections; programmable stages has to be utilized while using voltage measurement mode 3LN-LLy as follows:

• Undervoltage protection function ANSI 27 will use the voltages measured by 3LN connection for one busbar section.
• The voltages from LLy connection can be utilized in programmable stages for Undervoltage protection (taking into consideration that only one line-to-line voltage (Vab) is available) for the other busbar section.

Released for: Schneider Electric Saudi Arabia