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Panels with motor operating mechanism control
Operating modes for racking the withdrawable circuit-breaker
For safe and consistent operation, it is not possible to rack the withdrawable circuit-breaker manually and
electrically at the same time. This is ensured via two mechanisms.
First, the panel automatically blocks access for electrical operation when the control door (1) on the high-
voltage door is open. To prevent accidentally blocking access for electrical operation, the control door has to
be padlocked (3, 4) when the panel is set to the electrical racking for normal operation. This measure also
prevents accidentally stopping the motor, for example during an ongoing electrical racking procedure by
opening the control door.
Fig. 349: Circuit-breaker type 3AE1:
control door padlocked
Second, the user is required to select the appropriate access mode before racking manually or electrically.
Once an access mode is selected, the mechanism blocks access for manual racking and releases access for
electrical racking, and vice versa. However, it is important to stress: When access is released for electrical
racking, it is not until the control door is closed that this operating mode becomes active. A third mode blocks
any racking altogether as a precondition for opening the high-voltage door.
An indicator on the high-voltage door informs about the selected access mode:
,
Fig. 351: Control door open,
access mode indicator visible
206
1
2
3
4
Fig. 350: Circuit-breaker type 3AE5:
control door padlocked
NXAIR M
(1) Control door
Type 3AE5:
(2)
handle
Type 3AE5:
(3)
appliance for fitting
padlock
Type 3AE1:
(4)
handle with padlock
Fig. 352: Access mode indicator for
racking: possible indications
139-2021.9 / 07
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