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Description
4000481-04
9
3.4
Models
Circuitry of the pump heads:
Two-stage (Z):
Both pump heads are connected in series.
Ultimate pressure
Model
< 8 mbar
MPC 301 Zp Ex
Three stage (T):
The two pump heads are connected in parallel, two further pumps
in series.
Ultimate pressure
Model
< 2 mbar
MPC 601 Tp Ex
Note:
The three-stage model of the diaphragm pump is fitted with a by-
pass and a non-return valve parallel to the second and third stages.
These serve to relieve any intermediate compression which may
occur at the start or while working in the upper pressure range.
During maintenance or repair, ensure that they are fitted in the cor-
rect position and that they function correctly according to the wiring.