Please refer to the figure below for pump switching logic (F4.28 = 0, F4.29 = 0).
This pump switching logic can also be inversed via F4.29 or different terminal
connecting from relay. Effective Vg F4.38 will be calculated according to this
switching logic, this is a read only parameter.
Fig. 7-14: Action logic of relay
Δp = p
cmd
- p
actual
When the pump logic has been switched to different logic (Vg
max
or Vg
min
), the
control parameter need also to be changed:
For logic Vg
max
:
●
Effective Vg [F4.38] = Vg1 (two points) or Effective Vg [F4.38] = Vg1 + Vg2
(double pump)
●
p/Q controller parameter set [0], e.g. [F3.10]...[F3.19]
For logic Vg
min
:
●
Effective Vg [F4.38] = Vg2 (two points) or Effective Vg [F4.38] = Vg1 (double
pump)
●
p/Q controller parameter set [1], e.g. [F3.30]...[F3.39]
When the two points / double pump control is active, the p/Q pa-
rameter selection function via digital input (F2.16...F2.24) is deacti-
vated.
Application example:
24V power supply, normal open relay terminal Ta, Tb and Rexroth two points
pump controller is connected in series, [F4.28] is set to ''0: Two points pump''
and [F4.29] is set to ''0: Positive'', when Δp and N
th
satisfy the condition of relay
action, pump switches to the minimum displacement.
FcP 5020
Bosch Rexroth AG
Block Diagram of Main Functions
DOK-RCON03-FCP5020****-QU04-EN-P
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