DVR Faulty

Hello there, i work for a clay factory and we have two CAT Generator Sets, 500kVA and 1000kVA (C32). Once the 500kVA genset was overloaded and the voltage dropped to 41V line voltage. I simply switched it off and re-started it again and the voltage went back to the expected 415V line voltage. Recently the C32 was overloaded and the voltage dropped to 52V line voltage. I switched it off and re-started but it has since then not gotten back to the expected line voltage. It still gives 52V line voltage. Could it be that the DVR is in latched mode and needs reconfiguring or what??? Thanking you in advance.