8 Servicing/Maintenance
47 of 92
KSB Delta Macro
1983.843/04-EN
8.3 Setting the pre-charge pressure
WARNING
Wrong gas
Danger of poisoning!
▷
Use only nitrogen to charge the accumulator.
CAUTION
Pre-charge pressure too high
Damage to the accumulator!
▷
Observe the manufacturer's product literature (see name plate or operating
manual of the accumulator).
The accumulator’s pre-charge pressure (p) must be lower than the set start-up
pressure (p
E
) of the pressure booster system.
The best storage volumes are achieved with the following settings (mean value):
▪
Value 0.9 at start-up pressure > 3 bar
▪
Value 0.8 at start-up pressure < 3 bar
Example 1
p
E
= 5 bar
5 bar × 0.9 = 4.5 bar
With a start-up pressure of 5 bar the pre-charge pressure of the accumulator must be
4.5 bar.
Example 2
p
E
= 2 bar
2 bar × 0.8 = 1.6 bar
With a start-up pressure of 2 bar the pre-charge pressure of the accumulator must be
1.6 bar.
Checking the pre-charge pressure
1. Close the shut-off elements fitted underneath the membrane-type accumulator.
2. Drain the membrane-type accumulator via the drain valve.
3. Remove and store the protective cap of the membrane-type accumulator valve.
4. Check the pre-charge pressure using suitable equipment (e.g. tyre pressure
gauge).
5. Fit the protective cap of the membrane-type accumulator valve.
Filling the membrane-type accumulator
1. Remove and store the protective cap of the membrane-type accumulator valve.
2. Add nitrogen through the valve.
3. Fit the protective cap of the membrane-type accumulator valve.
