0 troubleshooting – Alpha Technologies AlphaCell HP User Manual

Page 24

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745-680-C5-002, Rev. A

24

5.0 Troubleshooting

Problem with

Symptom

Possible Causes

Possible Result

Corrective Actions

Capacity Test

Results

Reduced operat-

ing time at 77°F

(25°C) with

smooth voltage

decline

Normal life cycle

Eventual failure to support the

load followed by potential for

shorted cells

Replace battery system

when at 70% of rated

capacity or before

Reduced operat-

ing time at 77°F

(25°C) with steep

voltage decline or

voltage plateaus

Individual low capacity cells

Reversed cells during discharge

Reversed cells will become very

hot and will not fully recharge

Replace the isolated low

capacity batteries

Excessive initial

voltage drop even

to the point of

dropping load in

the first several

seconds

Battery is extremely cold

Cabling is too small

gauge

High resistance

connections

Battery is undersized

Shorted cells

Excessive voltage drop

Cells will become hot, could

develop thermal runaway;

internal arcing could result in

an explosion

Heat the battery

Run parallel cables

or increase gauge of

cables

Clean and reassemble

connections

Add required parallel

strings

Replace isolated

units with shorts and

evaluate entire string

Visual Battery

Checks

Cover or container

crack

Handling or impact damage

Cell dryout or ground fault.

Potential internal gas ignition

Replace damaged unit.

Cover or container

explosion

Ignition of cell internal gasses

due to external source,

fusing, or internal conductive

path or internal spark due

to shorting. Potential exists

for ill-maintained batteries or

those left in service beyond

useful life.

Personal injury and equip-

ment damage at time of

explosion.

Failure to support load.

Replace damaged unit and

evaluate balance of string.

Burned area on

container

Crack in container wicking

electrolyte to grounded rack.

Ground fault

Could result in

personal hazard due to

conductive path to rack

smoke or battery fire

thermal runaway

Clear the ground fault and

replace defective unit. Evalu-

ate balance of string.

Permanently

deformed

(swollen) container

Thermal runaway possible

caused by high temp.,

environment, overcharging,

excessively high recharge

current, shorted cells, ground

fault, or a combination

Could result in the emission of

hydrogen sulfide, detectable as a

rotten egg odor, battery fire, and

inability to support the load

Replace the battery system

and correct the items leading

to the theramal runaway

condition

Rotten egg odor

Possible caused by high

temperatuare environment,

overcharging, excessively

high recharge current, shorted

cells, ground fault, or a

combination of these.

Odor is a product of thermal

runaway

Replace the battery system

and correct items leading to

thermal runaway condition

Melted grease at

terminals

Hot connections due to

excessive resistance caused

by loose connections, dirty

contact surfaces or corrosion

within connection

Excessive voltage drop

perhaps leading to short

operating time or damaged

terminals

In extreme case could lead

to melted terminal and

ignition of the battery cover

Clean and reassemble

connection if damaged

Replace batteries with

damaged terminals

Corrosion at

terminals

Possibly electrolyte leaking

from battery terminal seal

attacking the interunit

container

Increased connection resistance

and resulting increase in the

connection heating and voltage

drop at high rate discharge.

Disassemble connection,

clean, coat connecting

surfaces and terminal area,

seal with anti-oxidation

grease, reassemble the

connection. If leakage about

terminal area is obvious, the

battery should be replaced.

Table 2, Troubleshooting

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