Setting the air gap on the brake

If the air gap is wider than permitted, it must be readjusted.

Overview:

Size	Air gap target value	Maximum air gap	Minimum air gap
GM2	0.25 mm	0.6 mm	0.2 mm
GM4	0.3 mm	0.6 mm	0.2 mm
GM6	0.35 mm	0.6 mm	0.3 mm
GM8	0.35 mm	0.6 mm	0.3 mm

Air gap (between magnet body and anchor plate)	Brake lining thickness

Magnet body and anchor plate	Brake rotor with brake lining

As soon as the chain hoist stops running, the anchor plate presses against the brake rotor by spring force, braking the motor. An air gap is created between the magnet body and the anchor plate. When the chain hoist starts up, the magnetic body pulls the anchor plate away from the brake rotor and the motor can rotate freely again.

If the brake lining is worn, the air gap will be larger. See page 33. If the air gap is larger than the maximum permitted, the brake must be readjusted. If the brake lining on the brake rotor is worn too thin, it must be replaced. See page 69.

Removing the chain box

	Bolt

		Chain box

Release the SL safety clip(s) (1x or 2x) from the bolt.

Hold the chain box firmly and pull out the bolt(s) (1x or 2x).

Remove the chain box.

Opening the chain hoist


Bayonet nut	Motor cover

Release the bayonet nuts.

Detach the connection cable and control cable.

Unscrew the motor cover from the housing.

● The fillister-head screws are secured by O-rings and thus do not fall out of the motor cover.

Detach the couplings of the hoist motor and brake from the control in the motor cover.

Uncovering the brake

Dust guard ring

Pull off the dust guard ring.

Setting the air gap

Hexagon head screws

Feeler gauge	Banjo bolts

Unscrew the hexagon head screws (3x) by a half turn.

Screw in the banjo bolts (3x) by a half turn in the direction of the magnet body.

Read off the set width of the air gap from the table.

Size	Air gap target value	Maximum air gap	Minimum air gap
GM2	0.25 mm	0.6 mm	0.2 mm
GM4	0.3 mm	0.6 mm	0.2 mm
GM6	0.35 mm	0.6 mm	0.3 mm
GM8	0.35 mm	0.6 mm	0.3 mm

Insert the appropriate feeler gauge directly next to one of the hexagon head screws in the air gap between magnet body and anchor plate.

Tighten the hexagon head screws so that the feeler gauge can still be pulled from the air gap.

● The air gap on this hexagon head screw is now adjusted to the set width.

Repeat the steps for all hexagon head screws (3x).

Concluding the setting of the air gap

Screw in the banjo bolts (3x) in the direction of the travel motor until hand-tight.

Tighten the hexagon head screws (3x).

Size	Size and length	Tightening torque
GM2	M4x45	3 Nm
GM4	M5x55	6 Nm
GM6	M6x65	10 Nm
GM8	M6x65	10 Nm

● The brake is fixed with screws.

Check the air gap next to all three hexagon head screws. If different than the set width, repeat the adjustment.

Covering the brake

Dust guard ring

Pull the dust guard ring over the brake.

Connecting the chain hoist

Attach the couplings of the hoist motor and brake to the pin multipoint connectors of the control in the motor cover.

Only connect couplings and pin multipoint connectors of identical colour (orange and grey).

For the assignment, see page 92.

With electronic hoist limit switch: Insert the connector on the hoist limit switch PCB.

Closing the chain hoist

Long fillister-head screws	Short fillister-head screw

Bayonet coupling		Motor cover

Hold the motor cover on the housing.

Note the different screw lengths and screw in the fillister-head screws.

Size	Size and length	Number	Tightening torque
GM2	M5x65	3x	4 Nm
GM2	M5x45	1x	4 Nm
GM4	M5x60	3x	4 Nm
GM4	M5x50	1x	4 Nm
GM6	M8x110	3x	15 Nm
GM6	M8x60	1x	15 Nm
GM8	M10x95	3x	20 Nm
GM8	M10x50	1x	20 Nm

Insert the bayonet coupling of the connection cable and the bayonet connector of the control cable. Due to a notch, the plug-in connections will only fit together in one position.

Slide on and tighten the bayonet nuts.

Only for GM2, GM4 and GM6 (GM6 with plastic chain box)

The illustrations show a chain box being installed on the GM6 chain hoist. Installation on a GM2 or GM4 chain hoist is very similar.

Installing the chain box

Bolt		SL safety clip

	Chain box

Place the chain in the chain box.

Turn the chain box as shown in the figure (slanted side facing outward).

Use the bolts to install the chain box on the chain hoist.

─ For GM2: Use a bolt to fix the chain box to the chain hoist.

─ For GM4 and chain box with one hole: Use a bolt to fix the chain box to the chain hoist.

─ For GM4 and chain box with two holes: Use a bolt to fix the chain box to the chain hoist. Use the inner holes of the chain box. The outer holes remain free.

─ For GM6 and plastic chain box: Use two bolts to fix the chain box to the chain hoist.

Secure the bolts with the SL safety clips (1x or 2x).

Only for GM8

Attach buffer

		Suspension straps

Buffer	Bolt

Turn the buffer as shown in the figure (rounded side facing inward).

Push the buffer between the suspension straps on the chain hoist.

Push the short bolt through the outer holes of the suspension straps and the buffer.

Only for GM6 (GM6 with chain box with metal frame) and GM8

The illustrations show a chain box being installed on the GM8 chain hoist. Installation on a GM6 chain hoist is very similar.

Installing the chain box

Inner hole	Bolt

Chain box	SL safety clip

Place the chain in the chain box.

Turn the chain box as shown in the figure (bar facing outward).

Use the bolts to install the chain box on the chain hoist.

─ For GM6 and chain box with metal frame: Use a bolt to fix the chain box to the chain hoist. Use the inner holes of the suspension strap. The outer holes of the suspension strap remain free.

─ For GM8: Use a bolt to fix the chain box to the chain hoist. Use the inner holes of the suspension strap. The buffer is fixed to the outer holes of the suspension straps.

Secure the bolts with the SL safety clips (2x).