guard lock


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guard lock

[′gärd ‚läk]
(civil engineering)
(engineering)
An auxiliary lock that must be opened before the key can be turned in a main lock.
References in periodicals archive ?
The G9SX-SM monitors the motor's movement by its back electromotive force (BEMF), and outputs a signal to unlock the Guard Lock Safety Door Switch as soon as it determines that the motor has stopped moving.
CLOSING: A security guard locks the factory gates, right; and above, the BPI factory in Stockton Picture by IAN COOPER
INVITES ONLY: A security guard locks the gates of Stormont.
A security guard locks up for the last time at the Dome last night
The inspection work includes, but is not limited to the following structures; locks, dams, guard gates, guard locks, retaining walls, culverts and spillways.
The inspection work includes but is not limited to; locks, fixed dams, moveable dams, guard gates, guard locks, tainter gates, retaining walls, sluice gates, waste weirs, culverts and spillways.