Burkert Type 8693 - Manual (Page 97)

97
Start-up and operation of the
position controller Type 8692
22.3.2. CHARACT
select the transfer characteristic between input signal
(position set-point value) and stroke
Characteristic (customer-specific characteristic)
Use this auxiliary function to select a transfer characteristic with reference to set-point value (nominal position, CMD)
and valve stroke ( POS) for correction of the flow or operating characteristic.
Factory setting: linear
CHARACT SELEC linear
EXIT
ENTER
GP 1:25
GP 1:33
GP 1:50
GP 25:1
GP 33:1
GP 50:1
FREE
y 0 ->: 0.0%
y 5 ->: 5.0%
y 100 ->: 100%
EXIT
22)
Linear characteristic
Equal percentage characteristic 1:25
Equal percentage characteristic 1:33
Equal percentage characteristic 1:50
Inversely equal percentage
characteristic 25:1
Inversely equal percentage
characteristic 33:1
Inversely equal percentage
characteristic 50:1
User-defined characteristic, freely
programmable via nodes
Figure 46: Operating structure CHARACT
The flow characteristic k
V
= f(s) indicates the flow of a valve, expressed by the k
V
value depending on the stroke s
of the actuator spindle. It is specified by the design of the valve seat and the seat seal. In general two types of flow
characteristics are implemented, the linear and the equal percentage.
In the case of linear characteristics identical k
V
value changes k
V
are assigned to identical stroke changes ds.
(dk
V
= n
lin
⋅ ds).
In the case of an equal percentage characteristic an equal percentage change of the k
V
value corresponds to a stroke
change ds.
(dk
V
/k
V
= n
equalper
⋅ ds).
The operating characteristic Q = f(s) specifies the correlation between the volumetric flow Q in the installed valve
and the stroke s. This characteristic has the properties of the pipelines, pumps and consumers. It therefore exhibits
a form which differs from the flow characteristic.
22)
Input the nodes see "Inputting the freely programmable characteristic"
english
Type 8692, 8693