Model 5200 High-Level Orderpicker

Use the “Electrical Connector Locator Chart” on page5-20 to find electrical connectors on the lift truck.

Inspection

Whenever working on the lift truck, use care around wiring harnesses.

•Do not pull on the wires.

•Carefully mate and unmate all connectors.

•Do not pry apart connectors with unspecified tools.

•Examine and maintain any added materials used to dress or protect the wire. This includes spiral wrap, brackets, cable ties, fasteners, flexible conduit, and so forth.

•Check harness wires for abrasions, scrapes, nicks, damage from overheating or burns, or other general insulation damage.

•Replace the terminations with exposed wire visible at the connectors. Damaged terminations, exposed wires, or damaged connectors can cause operational failure of the lift truck.

During troubleshooting and repairs, it is sometimes necessary to unmate a connector, move a harness, cut a cable tie, or remove the wire from a bracket. Note carefully the location of the wire and all of the protective or securing attachments before moving the harness.

After repair, return or replace all of the protective or securing hardware to its original condition. Protective materials are necessary to provide reliable performan ce of the interconnect system.

There should be a wire marker at each termination. If the marker is missing or unreadable, remark the wire for easier identification.

NOTE: It is normal to find unused connectors for uninstalled options that have had heat shrink applied over them and are strapped to the harness.

Publication Number: 1043922B, Revised: 2 Sept 2015

Section 5.Troubleshooting Troubleshooting Wiring Problems

Section 5.Troubleshooting

Switches (General)

Switches (General)

Test/Inspection

Examine non-Hall Effect switches for signs of arcing, overheating, discoloration, cracking, or other physical damage. Replace the switch if you see such damage.

To test a switch, isolat e it from the electrical circuit. Do this by removing all the connections from the switch, making sure all wires are labeled and identified for reconnection.

Use an ohmmeter set to a low resistance scale to measure the resistance across the switch. In a closed position, the switch should be less than 1 ohm. In an open position, the switch should show a resistance greater than 10 megohms.

Hall Effect Switches

The limit switches and deadman switches used on this lift truck are Hall Effect switches. These switches consist of a transistor that is turned ON when a magnet is placed next to the base. (Keep in mind that the magnet is part of the switch assembly and can only be seen if the switch is disassembled.)

Model 5200 High-Level Orderpicker

The switch is powered as follows:

•+6 to +12 volts is applied to the positive (+) terminal.

•Battery negative is applied to the negative (-) terminal.

As shown in Figure5-1, when a magnet is not present, the transistor is OFF and the output lead (Deadman#1) is in a high state.

When a magnet is present, the transistor is turned ON creating a path from the DGND (-) terminal to the Deadma n#1 terminal. Terminal Deadman#1 becomes a negative (-) potential, or active.

Key Switch Inspection

With the battery plugged in and the key switch in the ON position, battery voltage B+ should be present on both terminals of the switch. Test the key switch with an ohmmeter after removing it from the el ectrical system. In the OFF position, the ohmmeter should read greater than 10 megohms, and in the ON position, the ohmmeter should read less than 1 ohm. If not, replace the switch.

Publication Number: 1043922B, Revised: 2 Sept 2015

Model 5200 High-Level Orderpicker

Electric Motor Tests

Motor Types

Refer to Figure5-3.

•A shunt-wound or series-wound traction motor has four external connections: two armature (A) and two field (S, E, or D).

•A series-wound lift motor has only two external connections because the armature and field windings are connected internally.

•A permanent magnet steer motor uses permanent magnets as fields and has only two external connections.

Section 5.Troubleshooting

Electric Motor Tests

NOTE: Field connections may be labeled S. Shunt-wound motor field connections may be labeled E. Series-wound motor field connections may be labeled D.

Inspection

Inspect the commutator for surface condition and high mica. Most armatures have the mica undercut. If the armature on your motor does not, do not attempt to cut it.

The commutator must be smooth and clean to provide maximum brush life. When commutators are not correctly maintained, carbon dust can collect in the grooves between the segments. This can lead to a short circuit in the armature.

Remove the brushes from their box. Inspect the contact surface and brush length. If the brush surface has groove(s) or pit marks, it indicates the presence of a burr on the commutator surface.

Good commutation is indicated by a dark brown polished commutator and an evenly polished brush wearing surface. See “Commutator Surfaces” on page5-10.

If the commutator appears rough, pitted, or has signs of burning or heavy arcing between the commutator bars, remove the motor for servicing.

Publication Number: 1043922B, Revised: 2 Sept 2015

Section 5.Troubleshooting

Electric Motor Tests

Servicing

Some conditions, identified in Table5-1, may be resolved by cleaning the commutator with a special polishing stone. Polishing the commutator should only be attempted for the

Model 5200 High-Level Orderpicker

specified conditions. Refer to “Polishing the Commutator” on page7-62 for instructions.

Some conditions can be resolved by recutting the commutator on a lathe. This requires special equipment and training and should only be attempted at a qua lified DC motor repair facility.

Good Condition-Light Film

Uniform coloring indicates satisfactory operation of the machine and brushes. Acceptable film color may vary from light to dark due to film thickness.

Satisfactory Condition-Light and Dark Pattern

This condition can appear in alternating bars as shown or every 3rd or 4th bar. This is caused by imbalances in the windings or other motor variances. It is not an indication of commutator problems. The motor should have no issues running, but the condition may indicate a need for more frequent inspections.

Unsatisfactory Condition-Streaky Film With No Commutator Wear

Threading or streaked film on the commutator surface. May be accompanied by rattling or loud operation. This condition is frequently due to incorrect brush grade. Environmental conditions, such as freezer or low humidity, can be a contributing factor. This condition may be repaired with a polishing stone if caught soon enough. Refer to “Polishing the Commutator” on page7-62

Unsatisfactory Condition-Uneven Film

Patchy colors of varying densities and shape. This condition is generally due to unclean operating conditions and does not indicate damage to the commutator. Clean the commutator with a polishing stone and compressed air (see “Polishing the Commutator” on page7-62). Consider more frequent scheduled maintenance intervals.

Unsatisfactory ConditionFilm With Dark Areas

Dark areas can be isolated or regular. This condition indicates a commutator is out-of-round. Continued use may result in failure and damage to other systems. The motor should be replaced or recut at a qualified repair facility.

Unsatisfactory Condition-Example of Incorrect Commutator Machining

Bars are low on entry and leaving edges causing the brushes to ride on the middle of the bars. Continued use may result in failure and damage to other systems. The motor should be replaced or recut at a qualified repair facility. Consider more frequent scheduled maintenance intervals.

Publication Number: 1043922B, Revised: 2 Sept 2015