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Installation, commissioning and operating instructions for valve-regulated stationary lead-acid batteries
7140203153 V1.4 (09.2018)
Installation, commissioning and operating instructions for valve-regulated stationary lead-acid batteries
7140203153 V1.4 (09.2018)
2.3.4 Electric shock and burns
Danger!
Batteries can cause severe electric shock. If there is a short circuit, very strong currents may
be present. Do not touch any bare battery components, connectors, clamps or terminals.
In battery systems with a nominal voltage of over 1,500 V DC, you must provide equipment
for splitting the batteries into cell groups with voltages lower than 1,500 V DC. In order to
prevent serious injury as a result of electric shock or burns, be very cautious when performing
any work on the battery system.
Always wear the recommended protective clothing (insulated rubber gloves and rubber shoes,
etc.) and always use insulated tools or tools made of non-conductive material.
Remove all wrist watches, rings, chains, jewelry and other metal objects before working with
batteries.
Before conducting work on the battery system...
Determine whether the battery system is grounded. We do not recommend this. If the system is grounded,
terminate the connection.
Touching a grounded battery by mistake can result in severe electric shock. This risk can be significantly redu-
ced by removing the ground connection. However, the racks (or cabinets) used to hold the batteries do need to
be well grounded or completely insulated.
If a battery system is grounded…
There is a voltage between the ground and the ungrounded terminal. If a grounded person touches
this terminal, there is risk of fatal injury. There is also a risk of short circuit if dirt or acid on the
ungrounded terminal come in contact with the battery rack.
If an additional ground connection is made by some cells within the (grounded) battery system,
there is a risk of short circuit, fire and explosion.
If a battery system is not grounded…
If an accidental ground connection is made by some cells within the battery system, voltage is
created between the ground and the ungrounded terminal. The voltage can be dangerously high -
risk of fatal injury due to electric shock.
If a second accidental ground connection is made, there is a risk of short circuit, fire and explo-
sion.
If you have questions about these instructions or any other questions regarding safety when
working with a battery system, please contact your local HOPPECKE representative. You can also
contact us at our head office directly.
2.3.3 Electrostatic discharge
All lead-acid-batteries produce hydrogen and oxygen while operating, particularly during charging. These gases
leak from the battery in the ambience. Based on the mandatory natural or technical ventilation it can be assu-
med that a flame able oxyhydrogen concentration exists only in the close proximity of the battery. A flame able
mixture of oxyhydrogen always exists inside the battery cells. This effect does not depend on the battery techno-
logy, design or manufacturer, rather than a specific characteristic of all lead-acid batteries. The energy needed
for an ignition of oxyhydrogen is quite low and can be caused differently. Examples: Open flame, fire, glowing
sparks or flying firebrands from grinding, electric spark from switches or fuses, hot surface areas >200 °C
and – an underestimated cause – electrostatic discharge.
Measures to avoid the ignitions of detonating gas through electrostatic discharges
The development of electrostatic discharges on the battery or on your body or on clothes can be avoided if you
consider the information below:
Do not wipe the battery with an arid fabric especially made of synthetic material.
Rubbing on surfaces of plastic material (battery jars are typically made of plastic material) causes
electrostatic charges.
Clean the surface of batteries with water- moistened cotton fabric only. By using a water-moiste-
ned cotton fabric you avoid the buildup of electrostatic charges.
While working on batteries do not rub your clothes (e.g. made of wool) on the battery. Thereby
electrostatic charges could build up on the battery jar, your body or on your clothes.
Wear suitable shoes and clothing with special surface resistance that avoid the buildup of elec-
trostatic charge. Thereby the buildup of electrostatic charge on the body and clothing can be
avoided.
Do not remove self-adhesive labels, from the battery without special safety measures.
Removing plastic labels can build up electrostatic charges, which can ignite oxyhydrogen gas.
Before pulling off the label, wipe the battery moist.
