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➤ Do not lay tools on the battery. This can lead to short circuiting, overheating and battery burst‐
ing!
➤ Take particular care when the battery has been in service for a long time or has just been
charged, as highly explosive gas is emitted!
Ensure adequate ventilation!
10.4.9.2 Ensuring the batteries are charged
The battery may be subject to self-discharge if the machine has been out of operation for an exten‐
ded period. The starting voltage is insufficient to start the engine when needed. Moreover, exhaus‐
tive discharge of the battery can result in battery damage.
Always consider the following for starter batteries:
Recharge if stored for 30 days or longer!
The current charge level of the starter battery can be read from the operating mode
Battery
voltage at the SIGMA CONTROL SMART display.
Starter battery charge level:
Charge level [%] Voltage
display [V]
Electrolyte
density [lb/gal]
Notes
100
12.7 - 12.85
10.60
Battery OK,
fully charged.
75
12.5
10.35
Recharging required!
65
12.4
10.18
50
12.3
10.09
Limit of starting capacity!
25
12.0
9.68
Battery discharged below permitted dis‐
charge limit.
20
11.9
9.51
0
11.6
9.09
Battery permanently damaged due to total
discharge!
Values 77° F
Tab. 98 Starter battery charge level
➤ Check battery charge and recharge with appropriate charging device, if necessary.
10.4.9.3 Battery removal and installation
Precondition The machine is switched off.
The machine is standing level.
The machine is fully vented, the pressure gauge reads 0 psig.
The machine has cooled down.
The «battery disconnect switch» is turned off.
1.
There is danger of batteries bursting!
A short-circuited battery heats up quickly and can burst.
➤ Never short-circuit a battery (e.g. with a hand tool).
➤ Wear gloves and eye protection.
10 Maintenance
10.4 Drive engine maintenance
144
Operator Manual Portable Rotary Screw Compressor
MOBILAIR M82 SIGMA CONTROL SMART
No.: 901783 08 USE