Valid from: 15.02.2021 / Source: VAM-UM-00551-EN-04
Despite careful checking, we cannot exclude the possibility of errors in this document and we accept no liability for the information it contains.
Page 18
Reconnecting the magnetic coupling
This piston-type volume flow meter is less sensitive to impacts and vibrations than other float-
type designs.
The magnetic coupling dispenses with the need for a mechanical connection, which may
become worn or loose over the lifespan of the measuring device.
However, a pressure spike or sudden increase in volume flow may cause the piston magnet to
move at such a high velocity that the piston magnet (4) and the external display ring (5)
(see
Table 1, page 4)
become detached.
If this happens, use one of the following methods to reconnect the piston magnet and the
external display ring:
Caution!
The manufacturer’s documentation for the hydraulic system must be
followed.
If the system allows it, change the volume flow from "min. to no flow rate" to "max.
flow rate" so that the moving piston magnet (4) reconnects with the display ring (5)
magnetically.
In the case of heavily cyclical applications in which frequent decoupling can occur,
please contact one of the technical service staff for further recommendations.
Maintaining the pressure loading unit
Loading valve
If the loading valve (1)
(see Figure 7, page 11)
does not build up any load pressure in the
system, remove the load valve from the pressure loading unit. Check it for any foreign bodies
and worn parts or seals. Check the burst pressure protection (5)
(see Figure 7, page 11).
Replace
the defective burst pressure protection, see the “Replacing the safety disc” section on page 19
Volume flow meter
If no volume flow is displayed on the volume flow meter (2) (
see Figure 7, page 11
), this may
indicate a clogged piston assembly (2) (
see Table 1, page 4
). Remove any material that might
prevent the piston from sliding. Note the “
Reconnecting the magnetic coupling”
section on
page 18.
Note the “
Dismantling and cleaning the volume flow meter”
section on
page 1.
If the volume flow meter still does not show any flow, return the measuring device to the
factory for inspection.
Replacing the safety disc
Power meters of the type:
HK 7xx Sxx TKV
made from stainless steel are equipped with overload
protection. This overpressure protection is located in the pressure loading unit. (
Burst pressure
protection
(5), see
Figure 7, page 11)
