This machine, electric power relay can suck, protection, after a few seconds each voltage measurement P board, found STBY7V standby voltage is normal, the main supply voltage 24 v, measure the main IC830 switch power supply of 300 v 1 foot, four feet have 20 v starting voltage, static measurement IC830 peripheral short-circuit phenomenon, found no doubt IC830 damaged, replace IC830, boot up OK.nGpservice manual download site