Dungs 273061, Инструкция по эксплуатации

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MC • Edition 04.19 • No
. 278 349
6.4 Accuracy class / lock-up pressure class
The AC and SG data, in compliance with EN 334, do not
make any statement about the modulation range. Knowl -
edge of the minimum and maximum volume flow is essential
for the application in the field. Therefore, the accuracy val -
ues 'control quality' and 'lock-up pressure class' that can be
guaranteed at a volume flow of 1:10 were determined. The
Abbrevia-
tion
Description
AC Accuracy class
p
d
Outlet pressure
p
u1/2
Inlet pressure
p
ds
Set nominal value of the outlet pressure
SG Lock-up pressure class
Q
min / pu1/2
AC minimum flow volume at a specific inlet pressure p
u
(lower limit of the volume flow at which the stable
operating conditions for a given nominal value within the given operating temperature range).
Q
max / pu1/2
AC maximum flow volume at a specific inlet pressure p
u
(upper limit of the volume flow at which a given
accuracy class for a given nominal value within the given operating temperature range).
AC values of the table mentioned above refer to the maxi -
mum admissible percentage deviation of the outlet pressure
from the set nominal value, at which Q
max
≤ 10 is observed.
p
d
Q
min, pu1
Q
p
u1
Q
min, pu2
Q
max, pu1
Q
max, pu2
p
u2
p
ds
p
ds
x (1-AC/100)
p
ds
x (1+SG/100)
p
ds
x (1+AC/100)