Does the Sepam series 40 keeps the internal time in case of loss of the auxiliary supply?
Issue
A user wants to know whether a Sepam Series 40 relay retains its internal clock and stored data when the auxiliary power supply is lost.
Product
- Sepam Series 40 Protection Relays
Environment
- Sepam Series 40 devices operating with auxiliary power supply
- Power outage or loss of auxiliary supply conditions
Cause
When the auxiliary supply is lost, the relay can no longer actively power its internal functions. Retention of the internal clock and disturbance recording information depends on the hardware design and backup energy storage components incorporated in the device.
Resolution
For Sepam Series 40 relays:
- Units released before mid-2010:
The internal clock is maintained by a capacitor for up to 24 hours following a power outage. - Units released after mid-2010:
An additional capacitor was added to the design, allowing disturbance recordings to be retained for up to 48 hours after a power outage.
Additional information:
- Sepam parameters and protection settings are stored in non-volatile memory and are therefore retained even when power is removed.
- Other operational and event-related data are also stored in non-volatile memory. Refer to the applicable product documentation for details regarding the specific data types retained during a power outage.