VACUUBRAND MZ 2C EX +IK+EK - Manual (Page 9)

page 9 of 75
Documents are only to be used and distributed completely and unchanged. It is strictly the users´ responsibility to check carefully
the validity of this document with respect to his product. manual-no.: 999128 / 29/04/2014
☞ To control the faultless function of the diaphragm it could be recommendable
install a gas specific detector at the outlet of the inert gas purge. A signal from
the detector indicates a diaphragm crack. Switch off the pump immediately and
check diaphragms.
☞ It is possible to leave out the inert gas purge if the surrounding of the pump is
zone 2 or not an explosive atmosphere.
☞ Without inert gas purge the pump outer part has the specification II 3G IIB T4 X.
Gas ballast
☞
Use only inert gas for gas ballast.
☞ We recommend the use of gas ballast when pumping condensable media.
☞ Gas ballast connection lines (inlet and outlet) have to be performed conductive
grounded and gas tight (designation of the pump connections see figures).
☞ Connect the inert gas connections at the gas ballast and the crankcase not serial
but parallel.
☞ Provide an external pressure limitation to a pressure of 1.1 bar absolute if inert
gas is connected to the pump or at an air admittance valve. The inert gas has
to be dry and pure. It could be recommendable to provide an appropriate control
system to supervise the inert gas flow which switches off the pump in case of
failure (e. g. absence of inert gas) if necessary.
Pumping at high inlet pressure may lead to overpressure at the gas ballast valve.
☞
Pumped gases or condensate might be pushed out in case the valve is open.
☞ The inert gas lines have to be chemical resistent due to possible backflow.
Electrical connection
☞
Electrical connection of the pump must be performed only by a suitable trained
and supervised personnel.
☞ The motor cable for pumps in 230V version contains wires colour coded as fol-
lows: green or green and yellow: earth; blue or white: neutral; brown or black:
live.
☞ Provide a fuse for the mains cable (L and N) according to the current draw of the
motor, see ”Technical data”.
☞ The earth connection of the device (potential equalization) has to be performed
only using the green or green/yellow earth connection wire. Connect the earth
connection wire of the device to the earth connection of the power supply line and
the potential equalization point of the environment of the device.
☞ When using pumps with two motors absolutely connect both motors as described
above. Ensure that always both motors are running.
Inert gas purge
☞
The user must take suitable precautions to prevent any formation of explosive
mixtures in the expansion chamber using inert gas to purge the housing. Other-
wise in case of a diaphragm crack, mechanically generated sparks, hot surfaces
or static electricity may ignite these mixtures.
☞ Inert gas connection lines (inlet and outlet) have to be performed conductive
grounded and gas tight (designation of the pump connections see figures).
☞ Connect the inert gas connections at the crankcase not serial but parallel.
☞ We recommend an inert gas purge of ≥ 1 l per minute.
☞ Provide an external pressure limitation to a pressure of 1.1 bar absolute if inert
gas is connected to the pump or at an air admittance valve. The inert gas has
to be dry and pure. It could be recommendable to provide an appropriate control
system to supervise the inert gas flow which switches off the pump in case of
failure (e. g. absence of inert gas) if necessary.