The unlocking motion of the Cutsforth Brush Holder automatically disengages the terminal. This allows for the safe and easy removal of the brush holder with one hand.
Replacing a Cutsforth Brush Holder consists of these main steps:
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While maintaining control of the brush holder (A), pull the handle (B) and rotate it to the retracted position (C).
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Pull the brush holder (A) completely off of the holder mount (D) and ensure the terminal connection area (E) on the mount is not excessively worn or pitted.
It is normally not necessary to remove a brush holder for inspection prior to changing a worn brush. Watch for the following indicators of a problem:
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Inspect for arcing from the trailing edge of the brush.
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Inspect for discolored brush leads.
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Use a strobe to inspect for brush photographing (imaging) on the ring.
The frequency of inspections is unit specific and ranges from every day to once per week.
When the brush holder is removed, complete these inspections to ensure that the brush holder is in proper working condition:
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Inspect the brush holder for any signs of wear or damage as well as any excessive build up of dirt or foreign material.
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Check for any cracking or breakage of components or welds.
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Ensure the brush catch is holding the brush in the brush box when the brush holder is disengaged from its mount. The brush catch is the feature inside the brush box that holds the brush when the holder is out of service.
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Confirm the “snap in” pressure when installing or removing the brush holder is relatively equal to the other brush holders.
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After the brush has been removed, inspect the sides of the brush for any signs of restrictions such as scrapes or drag marks.
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Inspect the inside of the brush box for obstructions such as box deformity, burrs, or carbon deposits. Clean the box using denatured alcohol. Remove carbon deposits using a plastic or wood object. Avoid using sharp objects or abrasive cleaners as these could damage the interior of the brush box.
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Pull the brush terminal (A) free from the terminal mount.
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Orient the brush key (B) to the correct position in reference to the brush holder.
Do NOT insert the brush key in this orientation:
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Slide the brush key (B) into the lower beam (C) of the brush holder.
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Press down onto a flat surface until the brush key (B) snaps into the brush holder.
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When the brush key is fully engaged into the brush holder, the old brush (D) easily slides out when you pull away the brush holder.
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Press in on the release tab (A) of the brush key (B) and pull it out of the brush holder. The brush spring release fingers grab the brush spring as the brush key is pulled out of the brush holder.
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Remove the old brush spring (C) and discard. If you have a spring containing a Brush Health Sensor, the spring and sensor can be reinstalled into the brush holder and reused for the life of the sensor battery.
Complete the steps in these sections to install a new brush:
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Insert a brush spring (A) onto the spring rib (B).
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Push until the spring hole (C) snaps onto the spring pin (D).
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Rotate the brush (A) so the terminal ears (B) point down.
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Insert the brush (A) into the holder (C) until the terminal ears (B) pass the brush spring.
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Rotate the brush (A) so the terminal ears (B) point up and start to insert the brush into the holder.
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Insert the brush the rest of the way into the holder until approximately 1/8 in (3.2 mm) extends out of the brush box, (A) .
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Insert the brush terminal (D) onto the terminal mount rib (E).
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To prevent brush binding, lead damage, and interference with the handle (A), position the brush leads (B) as shown:
Review these correct/incorrect examples for additional clarification:
Correct
Incorrect
In this correct example the brush shunts are formed straight up so that they will not catch on the box.
Do not position the brush leads as this example shows. In this position the leads will restrict free movement of the brush (hang up).
After a new spring and brush are installed, the holder is ready to be returned to service. Complete the steps in these sections to return the Cutsforth Brush Holder to service:
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Align the brush holder (A) with the grooves on the side of the holder mount (B) and slide into the holder mount.
These example images provide additional clarification:
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Rotate and lock the handle (C) into place while applying light pressure toward the collector ring (D).
This section provides visual examples of correctly and incorrectly installed brush holders.