S+S Regeltechnik THERMASGARD RTM Notice D'instruction page 7

G
Measuring transducers, calibrateable, with active output
Output: .................................. 4...20 mA
Connection: ............................ 2-wire connection
Working resistance: ................ Ra (Ohm) = (Ub -14 V) ⁄ 0.02 A
Output: .................................. 0 –10 V
Connection: ............................ 3-wire connection
Load resistance: ..................... minimum 5 kOhm
Accuracy: ............................... ± 0.4 K at +25 °C,
TEMPERATURE RANGES:
When selecting measuring transducer ranges,
it is necessary to ensure that the maximum temperatures
permissible for sensor ⁄ enclosure are not exceeded !
Ambient temperature for measuring transducers:
– 30 ...+ 70 °C
Apparent ohmic resistance = see load resistance diagram
SUPPLY VOLTAGE :
For operating voltage reverse polarity protection, a one-way rectifier or
reverse polarity protection diode is integrated in this device variant.
This internal one-way rectifier also allows operating 0 - 10 V devices on AC
supply voltage.
The output signal is to be tapped by a measuring instrument. Output
voltage is measured her against zero potential (O V) of the input voltage!
When this device is operated on DC supply voltage , the operating voltage
input UB+ is to be used for 15...36 V DC supply and UB – or GND for
ground wire!
When several devices are supplied by one 24 V AC voltage supply, it is to
be ensured that all "positive" operating voltage input terminals (+) of the
field devices are connected with each other and all "negative" operating
voltage input terminals (–) (= reference potential) are connected together
(in-phase connection of field devices). All outputs of field devices must be
referenced to the same potential!
In case of reversed polarity at one field device, a supply voltage short-
circuit would be caused by that device. The consequential short-circuit
current flowing through this field device may cause damage to it.
Therefore, pay attention to correct wiring!
otherwise ± 0.8 K
Load resistance diagram
800
700
600
500
400
300
250
200
50
10 15 20
Operating voltage (V DC)
Dependency of output voltage on output current
12
Ua (V)
10
8
6
4
2
0
0 0.5 1.0 1.5
Connecting scheme
Power supply
AC 24V~ 0V
DC 15-36V = GND
Connecting scheme
Power supply
AC 24V~ 0V
DC 15-36V = GND
Load resistance diagram
4...20 mA
Admissible
range
25 30 35 36 40
Ia (mA)
2.0 2.5 3.0 3.5 4.0 4.5
Individual operation
Circuitry
V
Parallel operation
Circuitry Circuitry