Endress+Hauser RMS 621 - Page 83

Applications
Number of measurement points
The number of measurement points vary according to the unit model and application. For further
details, please see the table for applications/measurement points.
In general, the following measurements are possible:
Up to 2 measurement points using the inputs (measurements) q, p, T
p
, T
w
, when using saturated
steam then up to 3 measurement points using the inputs q, p/T
p
, T
w
.
One measurement point is covered by the basic unit. Expansion cards are required if further
measurement points are to be added. Each expansion card is fitted with outputs
(analogue/impulse) for retransmission of process values. Relay outputs are also available.
Diagram/calculation formula
T
D
P
q T
W
E = q   (T
W
)  [h
D
(p
D
, T
D
) – hw (T
W
)]
E: Heat quantity
q: Operating volume
: Density
T
W
: Feed water temperature
T
D
: Steam temperature
p: Pressure (steam)
h
D:
Specific Enthalpy of steam
h
W:
Specific Enthalpy of water