Genie S-60 TraX Service Manual page 173

December 2013
How to Test a Coil Diode
Genie incorporates spike suppressing diodes in all
of its directional valve coils except proportional
valves and those coils with a metal case. Properly
functioning coil diodes protect the electrical circuit
by suppressing voltage spikes. Voltage spikes
naturally occur within a function circuit following the
interruption of electrical current to a coil. Faulty
diodes can fail to protect the electrical system,
resulting in a tripped circuit breaker or component
damage.
Electrocution/burn hazard. Contact
with electrically charged circuits
could result in death or serious
injury. Remove all rings, watches
and other jewelry.
1 Test the coil for resistance. See, How to Test a
Coil.
2 Connect a 10Ω resistor to the negative terminal
of a known good 9V DC battery. Connect the
other end of the resistor to a terminal on the
coil.
Resistor, 10Ω Ω Ω Ω Ω
Genie part number
Note: The battery should read 9V DC or more when
measured across the terminals.
Part No. 147753
d
c
c
3 Set a multimeter to read DC current.
Note: The multimeter, when set to read DC current,
should be capable of reading up to 800 mA.
4 Connect the negative lead to the other terminal
27287
Note: If testing a single-terminal coil, connect the
negative lead to the internal metallic ring at either
end of the coil.
5 Momentarily connect the positive lead from the
6 At the battery or coil terminals, reverse the
S-60 • S-65 • S-60 TRAX • S-65 TRAX
S-60 HC • S-60X • S-60XC
Section 4 • Repair Procedures
COIL
-
W
10
RESISTOR
a multimeter
b 9V DC battery
c 10Ω resistor
d coil
Note: Dotted lines in illustration indicate a
reversed connection as specified in
step 6
on the coil.
multimeter to the positive terminal on the 9V DC
battery. Note and record the current reading.
connections. Note and record the current
reading.
Result: Both current readings are greater than
0 mA and are different by a minimum of 20%.
The coil is good.
Result: If one or both of the current readings are
0 mA, or if the two current readings do not differ
by a minimum of 20%, the coil and/or its
internal diode are faulty and the coil should be
replaced.
MANIFOLDS
a
AMMETER
b
9V
BATTERY
b
-
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