THE HD 688T MODULAR TEMPERATURE TRANSMITTER, Merk : DeltaOhm[30 Jul. 2009, 21:09:30]
Keterangan
THE HD 688T MODULAR TEMPERATURE TRANSMITTER FOR SENSOR Pt100
WITH INPUT/OUTPUT AND POWER SUPPLY GALVANIC SEPARATION
Output analogue signal: 0÷20 mA / 4÷20 mA / 0÷10 Vdc
The HD 688T transmitter is built inside a 2-module DIN box for 35 mm asymmetric
guide. The module turns the signal coming from a Pt100 into an analogue signal
that can be sorted out through a jumper connection between 0÷20 mA, 4÷20
mA, 0÷10 V. The signal is galvanically separated among input, output and power
supply. The 3-way insulation of the module allows the prevention of reciprocal
influences in the presence of various measuring circuits.
The HD 688T transmitter is made up of the following stages:
- input stage including linearization of the curves and equalization of the resistance
of the line cable (3 wires) of Pt100, conversion from voltage into frequency;
- universal output stage through jumper connection, conversion from frequency
into voltage;
- power supply stage.
The configuration of the measuring range or the output signal can be modified
at any time, an outstanding feature being that any variation does not involve the
need to calibrate the transmitter again.
FEATURES:
INPUT: CONFIGURATION:
Input signal: Pt100 (IEC 751)
Measuring range:
-50...+50°C / 0...+50°C / 0...+100°C
0...+200°C / 0...+400°C
Measuring current: 1 mA
OUTPUT:
Output signals: 0÷10Vdc 0÷20 mA 4÷20 mA
Maximum load: 5 mA 500©
Output impedance: 0.1© 1M© 1M©
POWER SUPPLY:
Input voltage: 12÷24 V ± 10%, 65 mA
Linearity: 0.2%
Zero drift: 0.02%/°C referred to full scale
Full scale drift: 0.02%/°C referred to applied signal
Response time:
0.3 seconds at 63% of final value
1 second at 99.9% of final value
Insulation: 3kV at 50 Hz for 1 minute
Operating temperature:
-10°C...+50°C (the maximum temperature
in which electronics can operate)
Variation of jumper connections according to the output measuring range,
relative retouch trimmers for start of scale and full scale.
Measuring range Output
Setup of jumper connections
TRIMMER*
start
of scale
full
J1 J2 J3 scale
1 -50 ÷ 50°C 0÷10Vdc A A A RR1 RR2
2 0 ÷ 50°C 0÷10Vdc B A A RR1 RR2
3 0 ÷100°C 0÷10Vdc C A A RR1 RR2
4 0 ÷200°C 0÷10Vdc D A A RR1 RR2
5 0 ÷400°C 0÷10Vdc E A A RR1 RR2
1 -50 ÷ 50°C 0÷20mA A B A RR1 RR2
2 0 ÷ 50°C 0÷20mA B B A RR1 RR2
3 0 ÷100°C 0÷20mA C B A RR1 RR2
4 0 ÷200°C 0÷20mA D B A RR1 RR2
5 0 ÷400°C 0÷20mA E B A RR1 RR2
1 -50 ÷ 50°C 4÷20mA A B B RR1 RR2
2 0 ÷ 50°C 4÷20mA B B B RR1 RR2
3 0 ÷100°C 4÷20mA C B B RR1 RR2
4 0 ÷200°C 4÷20mA D B B RR1 RR2
5 0 ÷400°C 4÷20mA E B B RR1 RR2
* Multiturn trimmers RR1 RR2 are needed for slight calibration adjustments of
start of scale and full scale. If not strictly necessary it is advisable not to operate
them, calibration being already carried out in the laboratory.