ProMinent Sigma X Operating Instructions Manual page 62

Start up
Avoid particles
Using the integral relief valve
Priming against pressure
62
The valves may no longer close properly with feed
chemicals with a particle size of greater than 0.3 mm.
Install a suitable filter in the suction line.
–
CAUTION!
Danger due to incorrect use of the integral relief valve
The integral relief valve can only protect the motor and
the gear, and then only against impermissible positive
pressure that is caused by the metering pump itself. It
cannot protect the system against positive pressure.
– Protect the motor and gear of the system against
positive pressure using other mechanisms.
– Protect the system against illegal positive pressure
using other mechanisms.
CAUTION!
Danger of the integral relief valve failing
The integral relief valve no longer operates reliably with
feed chemicals having a viscosity of greater than 200
mPa s.
– Only use the integral relief valve with feed chemicals
having a viscosity up to 200 mPa s.
1. Hydraulically isolate the discharge line from the pump using an iso‐
lation device.
2. Turn the rotary dial on the integral relief valve in a counter-clockwise
direction as far as the "open" stop.
ð The excess pressure escapes through the hose connector.
3. Run the pump until the feed chemical coming out of the hose con‐
nector is free from bubbles.
4. Turn the rotary dial on the integral relief valve in a clockwise direc‐
tion up to the "close" stop.
ð The pump can be started.
When operating the integral relief valve close to the
opening pressure, a minimal overflow into the overflow
line can occur.