8
Parker Hannifin Manufacturing Germany GmbH & Co. KG
Pump & Motor Division Europe
Chemnitz, Germany
Axial Piston Pump
Series PV, series 47 and higher
Bulletin MSG30-3245-INST/UK
Installation manual
4. Standard pressure compensator with D03 interface, code ...MM1
The standard pressure compensator code ...MM1
has topside an NG6/Cetop 3/NFPA D03 interface
for the mounting of suitable pilot valves. This com-
pensator can for example be directly equipped
with a proportional pressure pilot valve for electri-
cal pressure setting (ordering code ...MMK, see
figure on page 10).
The pilot valve must be capable of pilot flows of ap-
prox. 1,2 l/min. Therefore a nominal flow range of
3 – 6 l/min is recommended. A too small as well
as a too large pilot valve can lead to unsatisfactory
compensator performance.
In addition the compensator can be equipped with
a directional control valve for stand-by (unload-
ing) functions (ordering code ...MMW, see figure
on page 10).
Please note:
when mounting accessories (e.g.:
proportional pressure pilot valve) or external (re-
mote) control the integrated pilot valve first must
be turned in to avoid too early pressure limitation.
interface NG6 DIN 24 340
compensator differential adjustment
lock nut
pressure adjustment
lock nut
5. Standard pressure compensator for accessory mounting, code ...MMZ
interface NG6 DIN 24 340
Version ...MMZ is designed especially for compen-
sator accessory mounting (ordering code PVAC...,
see chapter 12).
Because the accessory packages come with their
own pilot valves, this version has no integrated pilot
catridge to avoid unwanted interaction.
For more details on the different compensator
options see also the PV compensator spare parts
compensator differential
adjustment
lock nut
manual for compensator design 47, Parker bulletin
PVI-PVC-47-GB.pdf.
Note:
Checking and adjusting the compensator differen-
tial should always be done by using two pressure
sensors/gages. Measuring one pressure only
(pump outlet pressure) and assuming, that the
pilot pressure at fully unloaded pilot valve resp.
with unload proportional pilot valve is 0 bar can
lead to completely wrong adjustments.
The different pilot valves can cause even at the
nominal pilot flow (1,2 – 1,4 l/min) already signifi-
cant back pressures which add to the compensa-
tor differential.
Only if the pilot pressure chamber is completely
unloaded (e.g.: when one of the side plugs is
removed or the DCV is in stand-by mode) it can
be assumed, that the pilot pressure is zero and
pump outlet pressure is equal to the compensator
differential setting.