Bridge Interlocks

Front 1

this lamp lights only if the normal up limit fails and the hoist is stopped by the back-up max. limit. If this occurs, maintenance should be performed to correct the failure of the normal up limit.

Back 1

BACK UP HOIST LIMIT

Front 2

This lamp lights whenever the platform is over the reactor, one control rod is withdrawn, and the main grapple is loaded. When this light is on, the main hoist is inoperative

Back 2

Fuel Hoist Interlock

Front 3

This interlock is from the zone computer, which limits travel to defined zones to prevent the possibility of running the grapple into walls or objects in the pool

Back 3

Safety Travel Interlock

Front 4

This interlock prevents bridge revers motion when the auxiliary platform is approached

Back 4

Bridge Collision Interlock

Front 5

This light indicates a platform condition that transmits a signal to RC&IS Rod Block circuitry affecting control rod withdrawal. This signal will occur if the main hoist is loaded and the platform is over the core.

Back 5

Rod Block Interlock 1 & 2

Front 6

This interlock indicates a condition that prohibits travel towards the reactor (reverse direction). This condition will be present if the Mode Switch is in REFUEL position, a control rod is withdrawn, the grapple is loaded, and the platform is moving towards the reactor.

Back 6

Bridge Reverse Stop No. 1

Front 7

This interlock stops reverse motion when. 1) mode switch is in the Startup Position 2) The bridge is over or near the core

Back 7

Bridge Reverse Stop No. 2

Front 8

This signal indicates a system shutdown due to any one of a group of monitored conditions indicating a fault condition. (i.e. motor thermals tripped, etc)

Back 8

Fault Lockout