The present invention relates to {TAIL ~ a fail safe system} in a control unit for {HEAD ~ a reversible pump turbine apparatus} 
The present invention relates to { TAIL ~ a fail safe system } in a control unit for { HEAD ~ a reversible pump turbine apparatus }
OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD