4
Subject to technical modifications as
part of further developments.
1 Safety instructions
Carefully read through
the instructions before
putting into operation.
Observe the instructions and
keep them in an easily acces-
sible place for reference.
Safety instructions are iden-
tified by a dot F and must
always be observed.
F The charger must be set up
horizontally on a firm surface.
The location (e.g. shelf) must
be sufficiently stable.
Pay attention to unit weight.
F Protect the charger against
moisture.
F Do not cover the charger.
Set up the charger so that
there is a clearance of at least
15 cm on all sides for ventila-
tion purposes.
F Charge batteries only in well-
ventilated rooms.
F Avoid fire, naked flames and
sparks!
Explosive gases are produ-
ced during battery charging.
F If there is pungent smell
of gas:
Acute
danger of explosion!
Do not switch off the unit.
Avoid fire, naked flames and
sparks.
Do not remove the charging
clips.
Immediately
ventilate
room well.
Only for WL 20 E:
Set the control knob (4) to
the left-hand limit
position.
(minimum charging current)
English
After ventilation:
Pull out the mains plug.
Have the battery checked by
an after-sales service center
for Bosch products.
F The charger is exclusively
designed for charging fault–
free standard and mainte-
nance–free lead–acid batte-
ries with nominal voltages of
12 V or 24 V.
F Only tested batteries must be
connected in parallel for char-
ging.
F Do not charge maintenance-
free batteries together with
standard batteries.
F Batteries which are not sui-
table for charging must not be
charged!
F The rated battery voltage and
selected charging
must agree.
F The mains connection cable
and the charging leads must
be in perfect condition.
F The charger must only be
connected to a mains power
supply where the mains vol-
tage agrees with the voltage
rating on the rating plate.
F Comply with the instructions
of the vehicle manufacturer
when using the charger as a
starting aid and when char-
ging vehicle batteries!
F Wear protective goggles.
F Immediately wash off acid
splashes on the skin or clo-
thing with large quantities of
water. If necessary consult a
doctor.
F Unscrew the inspection plugs
of standard batteries before
the
battery charging.
F Never disconnect the char-
ging clips during charging.
F Never short-circuit the char-
ging clips.
2 Description
Maintenance–free batteries, stan-
dard batteries and exhausted batte-
ries can be charged with the power-
ful workshop charger WL 15 E and
WL 20 E with electronic characteri-
stic control.
f Polarity protection
In the event of incorrect polarity
or terminal short–circuit the
charging voltage remains swit-
ched off.
3 Operating elements
Illustrations are provided on
the last few pages of these
instructions.
1. Battery type selector switch
Maintenance-free batteries
voltage
Standard batteries
2. Voltage selector switch
12 V – 24 V
3. Ammeter for charging current
4. Only for WL 20 E:
Control
variable) for setting the charging
current
4 Charging batteries
In order to avoid excessive gas for-
mation, charging should take place
at ambient temperatures above
approx. 30 °C and, in the case of
older batteries, only in the switch
position for
batteries.
F Nevertheless if charging is
carried out in the position for
standard batteries
all circumstances charging
must cease when the battery
is fully charged.
knob
(continuously
maintenance-free
under