Warner Electric Wheel-Brakes (Std) User Manual
Page 14
14
Warner Electric • 800-825-9050
819-0514
Check for Lining Wear
To check for lining wear, apply the tractor hand con-
troller full on and back up the unit to set the trailer
brakes hard. Do not release the brake, but mark the rim
as indicated in Table II, page 15. Without releasing the
brake, move the unit forward to set the trailer brakes
hard, and again mark the rim as indicated in Table II.
Measure the dimension “A” on the curve of the rim.
Note:
The differences in loading and method
of measuring give only approximate results
which should be close enough to determine
whether the magnet is approaching
maximum travel and/or the lining is worn out.
For greater accuracy, it may be necessary to
disconnect all brakes except one and check
each wheel individually. After setting brake
as above, ease clutch off so as to allow
deflection of trailer suspension, caused by
brake application, to release.
If maximum travel based on Table II has been reached
and loss of brake power has been experienced, wheels
should be removed and the brakes relined.
Check Amperage at Each Brake
Amperage check at the controller should be followed
by an individual amperage check at each brake magnet
(Figure 3-5). When all brakes are connected in parallel,
connect the ammeter between either of the brake ter-
minals and the wire removed from that terminal. Make
light, fast controller application to insure that meter is
properly connected into brake circuit with respect to
polarity. The reading at each brake should be the same
and equal to the value given in Table I. If brakes are
connected in series on a given axle (tandem axle trailer
and 12-volt tractor), current per axle is equal to one
magnet based on Table I. To check each individual
magnet when series is connected, disconnect both
leads from one brake and connect ammeter between
the two leads. The reading per magnet should be
double that given in Table I. If current reading for any
one brake is incorrect, inspect for broken wires, dirty
or loose connections and shorts. Failure to find fault
externally, when brake amperage is incorrect, will
necessitate removal of wheel for further inspection.
Tire
Rim
Size
Nom.
“D”
(in.)
C
“A” Maximum
12-1/4 x 5-1/2
15 x 3
16 x 2-1/2
16-1/2 x 5, 6, 7
17-1/4 x 3
17-1/4 x 4, 5
15
14.7
7.8
8.15
16
15.7
7.3
8.7
18
17.6
6.5
9.75
8.6
20
19.6
5.85
10.8
9.6
6.0
11.3
9.1
12.3
22
21.6
5.3
10.5
6.6
12.45
10.0
13.5
24
23.7
4.87
11.6
7.25
13.65
10.9
14.8
Table II — Lining Wear
“A”
“A” Measured
Here
Inside
Rim
Dia.
“D”