Part No. 1104849
17
3G Storm Series
®
Wheelchairs
SECTION 2
TROUBLESHOOTING
This Section Includes the Following:
Field Load Test
Motor Testing
Motor Brush Inspection
Electro-Mechanical Parking Brake Testing
FIELD LOAD TEST (FIGURE 1)
NOTE: The following test can also be performed through the controller of the wheelchair along
with a remote programmer. Refer to the ELECTRONICS MANUAL
supplied with each wheel-
chair.
Old batteries lose their ability to store and release power, due to increased internal
resistance. This means that as you try to take power from the battery, some of that
power is used up in the process of passing through the battery, resulting in less voltage
at the posts. The more power drawn, the lower the voltage available. When this lost
voltage drops the output 1.0 volts under load (2.0 for a pair), replace the batteries.
Testing under load is the only way to spot this problem. While special battery load
testing equipment is available, it is costly and difficult to transport.
Use a digital voltmeter to check battery charge level at the charger connector. It is located
on the base of the wheelchair frame.
NOTE: READ the instructions CAREFULLY
before using the digital voltmeter.
NOTE: Invacare recommends that ONLY
qualified service personnel perform this test.
1. Ensure that power is OFF.
2. Make sure battery is fully charged. An
extremely discharged battery will exhibit
the same symptoms as a bad one.
3. Remove the footrests from the wheelchair and place the CASTERS of the wheelchair
against a wall, workbench or other stationary object.
4. Place the voltmeter leads into the charger plug on the wheelchair. Most digital voltmeters
are not affected by polarity, however, analog meters (meters with swinging needles) can be
and should be used carefully. A good meter reading should be 25.5 to 26 VDC.
5. Have two (2) individuals (one [1] on each arm) apply as much downward pressure as
possible on the arms of the wheelchair.
6. Turn the wheelchair ON and push the joystick forward, trying to drive the wheelchair
through the stationary object. This puts a heavy load on the batteries as they try to
push through the stationary object. Read the meter while the motors are straining to
determine the voltage under load.
NOTE: If the voltage drops to less than 23.5 volts from a pair of fully charged batteries while
under load, they should be replaced regardless of the unloaded voltages.
(+)
(-)
FIGURE 1 - FIELD LOAD TEST
Battery Charger
Connector
Digital Voltmeter
TROUBLESHOOTING
