COVER 2W8894 - Caterpillar

A6
This option is available on CTG units only. The option allows a load from a motor to be disconnected from the power source for a short period of time before a transfer between sources takes place. A load from a motor needs to be disconnected from a power source before the power is transferred to another source. Disconnecting the motor will ensure that the motor is not damaged. Damage to the motor can happen due to differences in the phase angles between the load and the new power source. The motors can be disconnected for an adjustable period of zero to sixty seconds prior to the transfer of the main contacts. This feature includes LED indicators that are used to indicate when the loads are disconnected.T3/W3
Illustration 1 g00823761
The T3/W3 option is not available on CTGD units.The auxiliary contacts close up five seconds before the transfer in either direction and the contacts open after the transfer. The contacts are located on R1 and/or R2. Refer to the illustration 1.Note: The pre-signal time is adjustable via the T3/W3 timers. See Service Information, "Timers".T3 is prior to the transfer to NORMAL.W3 is prior to the transfer to EMERGENCY.The T3/W3 is terminated when the transfer is due to an outage of the power source.