Turbine Protection Alarm activated last night. After the checking, here we found that;
- Protection Fault 01MAY10EU249XC8
- Calculated Trip Test Fault 01MAY10EU276XC9
- Protection Test Fault 01MAY10EU281XC9
At microrec, a lot of logics need becarefully check since the software history itself given much trouble to unit.
Discussed in detail among us this morning examining the risks in re-setting this alarm and the conclusion reached is minimal risk, to be extra careful should be carried out at low loads and after evening peak.
More detail: the protection listed above has a self checking routine usually every 12/24 hours, this sequence has hung up on detection of some parameter not giving expected results and requires re-setting. If not re-set valve freedom tests cannot be carried out. It is expected that the fault will re-appear within 12/24 hours ideally the fault should be re-set just before valve freedom tests. Clearing the defect requires detailed investigation with the unit off load.
Here is some short cut step when we clearing the alarm (Many steps are not reveal here);
1) BO4Y010P CON#302 f0r to '0'
2) PO4GNTRT #Safeties_Set force to '0' then unforce back the logic.
3) BO4Y31SE SEQ12*700 from state '11' back to '0'.
Work done.