MAC One: Bottom Plate Grounding Issue
Table of Contents
Brand:
- Martin
Affected Products:
- MAC One
Summary:
- Due to missing countersinks on the base housing screw towers, base housing screws could not properly secure the bottom plate, leading to potential ungrounded conditions on the bottom plate.
- Factory production stock and DC finished goods have been reworked. A change notice (CN180645) was implemented for factory base housing materials. For field units, special star washers must be installed at the bottom plate mounting points to ensure proper chassis grounding.
Troubleshooting:
Step 1: Symptom & Ground Verification
- Perform a grounding/hipot continuity test between the bottom plate and the rest of the fixture chassis.
- If continuity is missing or high resistance is measured, the bottom plate lacks sufficient ground contact.
Step 2: Resolution & Field Action
-
Rework / Workaround: Mount four star washers on the bottom plate screw locations to ensure proper ground contact with the base housing.
- Recommended Timing: It is suggested to inspect and install the star washers during routine maintenance, general service, or the next battery replacement.