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Drive stops all of a sudden without any indication.....
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Many a times, dc motor stops all
of a sudden, without giving any indication. On quite a few occasions, the
motor starts running again without doing anything. This is, most of the time,
due to poor electrical contact which “enables” the DC drive. Normally a closed contact is used to “enable”
the DC drive. If the contact resistance increases due to accumulation of
dust, such observations are commonly seen. By putting the Electrical Power
off, and doing resistance measurement of contact used for “enable” function
of the drive, reveals the cause of the problem. Resistance values more than 1
or 2 ohms indicates that the contact condition is poor and is likely to show
higher reisistance any time during operation. Cleaning the contact with
“Electrical Contact Cleaner” or CTC ( Carbon Tetra Chloride ) solves this
problem. Since the drive is disabled when
contact resistance is high, this does not blow fuses while the motor stars
running on its own again. Reference is again routed through ramp circuit and
motor does not experience jerks while restarting. Low values of Ramp
acceleration timing may blow fuses in such situtations. |
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Speed control not satisfactory
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