Siemens 6DR2410, Руководство пользователя

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1 Technical Description
1.5 Functional Description
1.5.8 Complex Functions (Arithmetic blocks c, d, h)
Manual
60
SIPART DR24 6DR2410
C79000-G7476-C153-03
Related to the correction factor it follows:
A
=
Δ
p

· f (E2, E3)

with F
=
f (E2, E3)

=
(PE
−
PA) E2
+
PA
(tE
−
tA) E3
+
tA

The measuring ranges are normalized to the calculation state with the parameters PA, PE, tA,
tE (correction quotients start/end for pressure and temperature).
Mass flow computer, qm
A = q
m
, E2 = p, E3 =
Â
PA
=
P
absA
P
B
, PE
=
P
absE
P
B
,
tA
=
T
A
T
B
, tE
=
T
E
T
B
with T
A
∕
E
∕
B
[K]
Volume flow computer related to the operating status q
V
Since the volume is reciprocally proportional to the density, a volume flow computer can be
made out of this mass flow computer by changing the inputs E2 and E3.
A = q
v
, E2 =
Â
, E3 = p
PA
=
T
A
T
B
, PE
=
T
E
T
B
with T
A
∕
E
∕
B
[K],
tA
=
P
absA
P
B
, tE
=
P
absE
P
B
Volume flow computer related to the standard status q
VN
Since the output signal is now related to the volume flow in the standard status, T
N
= 273.15 K,
P
N
= 1.01325 bar
abs
and no longer to the operating state, it must be corrected accordingly.
A = q
VN
, E2 = p, E3 =
Â
PA
=
P
absA
P
B
, PE
=
P
absE
P
B
tA
=
T
A
T
B
, tE
=
T
E
T
B
with T
A
∕
E
∕
B
[K],
The following applies for all computers:
p
absA
to p
absE
Transmitter range absolute pressure (bar)
T
A
to T
E
Transmitter range absolute temperature (K)
is formed from the transmitter range
Â
A
to
Â
E
by conversion:
T(K) = 273, 15 +
Â
(
_
C)