BOLT 6J6721 - Caterpillar

All Automatic Transfer Switches Described By 9Y-7900Reference: Operation And Maintenance Manual, SEBU6234-02, Caterpillar Automatic Transfer Switch (Contactor Type)Description of Change: A new optional programmable logic control with an in-phase monitor will replace the former optional programmable logic control board. The new control will operate similar to the former programmable logic control except during the transfer between the normal and standby power sources. Both the normal and standby power sources will be evaluated by the in-phase monitor and if they are in-phase a transfer will be allowed. If the required transfer conditions are not met in 10 seconds, then the system reverts to a delay neutral transfer.Adaptable To: The new 130-5692 Programmable Logic Control with an in-phase monitor will be available during the first quarter of 1996. The new 130-5692 Control cannot be adapted to existing transfer switches. The former 9Y-8013 Programmable Logic Control Board will continue to be a serviceable part, but will no longer be available as an option on new transfer switches. See the listed reference for further information on Automatic Transfer Switches and the new 130-5692 Programmable Logic Control with an in-phase monitor.