Siemens 3AH3 Operating Instructions Manual page 21

Mechanism box
Functions
Indicators
Siemens Parts
9229 9860 176 0E
2013-08-22
The mechanism box (60.) contains all the electrical and mechanical components
required to switch the vacuum circuit-breaker on or off. Insulating operating rods
(48.) transfer the switching movement to the pole assemblies.
The mechanism box is closed with a removable cover (60.1).
Fig. 25 Operating and indicator elements
50.1 Opening for hand crank
51. Rating plate
53. CLOSE pushbutton
54. OPEN pushbutton
55. Spring state indicator
There are openings in the cover (60.1) for the operating and indicator elements.
The CLOSE pushbutton (53.) is used to close the vacuum circuit-breaker. The motor
(50.4) immediately charges the closing spring (62.). If the supply voltage for the
motor fails, the closing spring can be charged with a hand crank (50.). There is an
opening (50.1) for this in the cover, behind which you will find the hand crank cou-
pling (50.5) of the gear unit (50.2).
The charged state of the springs is indicated via the spring state indicator (55.). The
position indicator (59.) shows the CLOSED or OPEN state. The operating cycle
counter (58.) indicates the number of operating cycles. An operating cycle consists
of one closing and one opening. The rating plate (51.) is attached to the mechanism
box and readable through an opening (51.1) in the cover.
58. Operating cycle counter
59. Position indicator CLOSED-OPEN
60.1 Cover
a) Tightening torque Md = 10 Nm
Description
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