Thales 421, Эксплуатация и обслуживание, Страница: 159 / 256

LLZ 421
Operation and Maintenance Maintenance
ILS 420
6−17
Ed. 01.10 SOAC
When purchasing mixed acid it may be that the quantity is specified in kilograms on the container.
The chart (Fig. 6−3) is however only valid for quantities specified in liters. Kilograms can be converted
to liters as follows:
Quantity in kg
Acid density in kg/l
Quantity in l =
6.4.1.2.3 Relationship between the Acid Density and the Temperature
The nominal acid density of fixed batteries is valid at an acid temperature of 20 °C. If the temperature
increases the density will be reduced by 0.0007 kg/l per °C; if the temperature falls it will be increased
accordingly. Thus if the temperature rises by 15 °C the density will be reduced by approx 0.01 kg/l;
if the temperature falls by 15 °C the density will be increased by approx. 0.01 kg/l. The chart (Fig. 6−4)
shows the acid densities for various temperatures in relation to a temperature of +20 °C.
Example: − measured density=1.23 kg/l
− measured acid temperature =+35 °C
The line between the two points intersects the middle scale at 1.24 kg/l
(density at reference temperature of +20 °C).
measured density
density at +20 °C
(reference temperature)
acid temperature
1,30
50
40
30
20
10
0
−10
−20
°C
1,25
1,20
1,15
1,10
1,20
1,25
1,15
1,10
1,30
1,35
kg/l
kg/l
Fig. 6−4 Chart showing the relationship between the acid density and the temperature
6.4.1.2.4 Basic Rules for handling Batteries
A few basic rules listed below should be observed when handling batteries:
WARNING
It is forbidden to use naked flames or incandescent bodies in the vicinity of accumulators.
This is particularly dangerous during the charging procedure, since oxyhydrogen gas is
produced when the gassing level of the accumulator acid is reached.
Caution should be observed when opening the inspection plugs. On no account should
salt crystals or other foreign bodies be allowed to get into the acid is reached.
Caution should be observed when topping up with specially purified water and when mea-
suring the acid density. Remove splashes of liquid, or conductive layers might form, allow-
ing creepage. Seal the inspection plugs again.
Maintenance−free batteries need not to be refilled. No acid density check is necessary.