b.In the event that both Power Supply No. 1 (24 volt DC) and Power Supply No. 2 (24 volt DC) fail, eventhough AC power is present, the power failure alarm will be operated. The same silencing and ringbackfeatures apply when generated by this means.7.15CondensateDrainEach operation of the condensate drain switch is indicated by an increment of 1 on the digital readout appearingon the front panel of the electronics drawer.The service log of the unit indicates the specified number of operations and permits verification of the operation ofthe condensate drain switch at the rate of approximately twice per calendar day.In the event of total power failure, the readout will automatically reset to zero. This fact should be noted and thedate of the occurrence logged.In the event the condensate drain switch mechanism fails, the following indications are available:a.If the condensate drain switch fails to turn the blowers off, the digital readout will not advance. Verification ofthe appropriate number of shutdowns of the blower is made by multiplying the number of days since thesystem was serviced by two. Digital readout should be within ten percent (10%) of that value.b.If the condensate drain switch turns the blower off and fails to restore it, the blower failure trouble signal willoccur on the panel. It will be indicated by both an amber blower failure lamp in the trouble group and acommon trouble signal, both visual and audible.The condensate drain switch is a separate printed circuit board which plugs into the main printed circuit board.Removal of this circuit board results in illumination of the timer disconnect trouble lamp and the common troublelamp plus the energizing of the common trouble signal plus blower shutdown.7.16Three switches and a fuse are located on the timer circuit board.NOTEOperation of these switches or replacement of the fuse is intended to be byfactory-trained servicement only and should not be attempted by the ship'spersonnel. Field service operations are normally restricted to the replacement ofthe entire circuit board.7-11
Integrated Publishing, Inc. - A (SDVOSB) Service Disabled Veteran Owned Small Business