remote control equipment - Indian Railways Institute of Electrical ...

light or bluish grey according to age the chief indications of weak cells are badly
coloured plates, irregularity in gassing or entire failure to gas and a fall in voltage and
specific gravity below that of other cells.
In new batteries, flakes of brown scale will be seen getting detached from
edge of positive plates. This information of scale is normal. Until all this scale is
dispersed, the plate cannot be considered as stabilized. Sometimes pieces of this
scale may lodge across adjacent negative plates and cause a partial short circuit.
Such flaked pieces should be gently dislodged with a thin piece of wool and allowed
to fall to be bottom of the cell. This scaling occurs only on the edges of the plates.
The removal of the scales should be done very carefully so that the plates are not
damaged.
Examine carefully the physical condition of the plates such as cracks,
distortions, accumulation of whitish deposits etc.
The colour of the deposits gives a good indication of the state of health of the
cells. Whitish deposits indicates undercharging leading to discharged condition. In
healthy cells, the deposit is brown in colour but excessive shedding of active material
from the positive plates indicates overcharging of the battery. If this is noticed,
reduce the rate of charge immediately. If all the cells in a battery show whitish
deposits immediate action should be taken to give boost charge at an appropriate
rate and then to increase the trickle charging rate sufficiently to keep the battery in a
healthy condition all the time. Weak cells should be immediately examined for any
possible short circuit or metallic contact between positive and negative plates. The
short circuit should be removed and the cell should then be given special additional
charging by cutting it out and putting it back again when a healthy condition is
regained, after it is attended to.
3.3.6.7. Inter-cell Connectors
The inter-cell connectors of the battery should be examined to ensure that
they are clean and tight, making perfect contact with cell lugs and that no corrosion
is taking place. Light Vaseline should be applied to prevent corrosion.
Inspection of copper inter-row connectors should be made for any signs of
copper sulphate corrosion which should be cleaned up. Acid-proof paint or enamel
should be applied to all exposed copper work in the battery room and any flaking of
paint work given prompt attention.
3.3.7. Protective Relays
1. Each electrified division shall have specialist staff attached to the
Central Repair Shop trained in the maintenance, overhauling, testing
adjustment and calibration of protective relays as well as indicating,
integrating and recording instruments. Such specialist staff should hold
competency certificate No TR-7 as explained in Chapter XII.
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