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Troubleshooting
BR/BD 75/140 R, BR/BD 90/140 R
New Unit Information 03.2004
Poor cleaning results
Adjust the contact pressure to the brush
rollers
– Loosen the cable gland (3), remove the retai-
ning screws (5) and the cover (4).
– Move piston (2) of the the lifting motor (1) in the
test mode to 32 ± 2 mm (1.25 ± .078 in). (Brush
head lowered, see test mode.)
– Adjust the cam (9) for activating the micro-
switch (7) to this setting.
– Extend the piston (2) of the lifting motor (1) to
115 ± 2 mm (4.49 ± .078 in). (Brush head rai-
sed, see test mode.)
– Adjust the cam (10) for activating the micro-
switch (6) to this setting.
– When setting the cams ensure that the piston
overshoot is approx. 2-3 mm (.078-1.18 in).
The cams (9) and (10) are fixed to the shaft (8)
of the variable speed motor by means of set
screws. When adjusting, note the rotational di-
rection of the shaft (8).
1
Lifting motor (M20)
2
Lifting motor piston
3
Connection cable gland
4
Microswitch cam cover
5
Cover retaining screws
6
Microswitch, piston extended
115 ± 2 mm (4.49 ± .078 in)
7
Microswitch, piston retracted
32 ± 2 mm (1.25 ± .078 in)
8
Lifting motor shaft (1)
9
Cam for microswitch (7)
10
Cam for microswitch (6)
32 ± 2 mm
(1.25 ± .078 in)
5
4
3
2
1
6
7
8
9
10
Brush head lowered (BR and BD)
Brush head raised (BR and BD)
Micro switches and cams
115 ± 2 mm
(4.49 ± .078 in)
Note:
The adjustment of the lifting motor (1) must
be done outside the unit.
We recommend that you extend the piston
(2) to approx. 75 mm (2.95 in) when changing
the brush head. In this setting the brush head
can be easily removed.