Endress+Hauser RMA 421 Mise En Service page 74

Process transmitter
6.4 Temperature measurement in a furnace
The temperature in a furnace is being measured using a thermocouple Type S
(PtRh-Pt) and displayed. The range of 1100°C to 1300°C is to be retransmitted
to a DCS in the form of a 4-20 mA current signal. A warning lamp illuminates
should the value go below 1150°C, below 1100°C the material feeder is
switched off.
n fault condition the current signal ramps to minimum safety. The terminal
temperature compensation point is used for cold junction compensation.
Example:
nput/Output:
- nput thermocouple Type S
- nternal temperature compensation
- 1100°C equals 4 mA
- 1300°C equals 20 mA
- Fault condition equals 3.6 mA at the analogue output
Set point 1:
- Minimum safety
- Switch point 1150 (°C)
- Hysteresis 10 (°C)
Set point 2:
- Minimum safety
- Switch point 1100 (°C)
- Hysteresis 50 (°C)
Setting up:
enu group
Analogue input
INPUT
Analogue output
OUTPT
Set point/fault monitor
Set point/fault monitor
72
Address
Input range
Curve
Comparison temperature
Output range
Scale analogue output 0%
Scale analogue output 100%
Fault operation
ode
LIM1
Set point
Hysteresis
ode
LIM2
Set point
Hysteresis
RANG
CURVE
COMPT
RANG
FAIL
MODE1
SETP1
HYST1
MODE2
SETP2
HYST2
Value
TYP5
°C
INT
4-20
11000
OUTLO
13000
OUTHI
MIN
MIN
1150,0
10,0
MIN
1100,0
50,0