Digital T/C Simulator Digisim 28543
The DigiSim 28543 is a portable, battery-operated, precision 4 digit simulator for mV & T/C input instruments. It is designed to source mV signals as well as simulate upto three specified T/Cs in international standards. In addition to simulation, it can also be used as a precision mV and Temperature Indicator. A self-check facility monitors its performance and assures its dependability.
The 28543 is designed with field-proven circuit blocks using low-power integrated circuits. It can operate on 7 AA size dry cells or AA size rechargeable Ni-Cd cells or an external Battery Eliminator. The battery voltage is monitored to provide low battery indication. A current limited DC/DC converter provides operating power to its internal circuitry for operational safety in hazardous locations. The 28543 uses two ten-turn potentiometers for setting the mV or T/C outputs and one for setting the CJ Temperature in its Manual CJ compensation mode. A 12 bit precision A/D converter provides binary output for addressing a ROM look-up table containing the mV and linearised temperature values which are presented on a 4 digit display. The entire measuring circuitry is designed to provide exceptional stability and repeatability. A self-check facility is provided to establish correct functioning of all the circuit blocks.
With the 28543 in Simulation mode, the mV output or the temperature of the simulated T/C can be set directly on the display by varying the COARSE & FINE potentiometers. For T/C simulation, the output is cold-junction compensated according to the characteristics of the simulated T/C. In the Measurement mode, mV or temperature of the connected T/C can be directly read on the display.
OUTPUT SPECIFICATIONS
The 28543 sources mV & T/C signals with the following specifications
Millivolts
80mV with a resolution of 0.02mV into 100O load
Thermo-couples
T/C types J, K, T, E, R, S, B or their combinations as follows
| I/O Display |
T/C Code |
Display Type Calibration |
Res Range |
Self-Chk |
Factory °C |
| J |
Fe / Const |
- 50 to 600 |
1 |
555 ±1 |
ISA/ANSI |
| K |
Cr / Alumel |
- 50 to 1200 |
1 |
1111 ±1 |
ISA/ANSI |
| T |
Cu / Const |
-50 to 400 |
1 |
333 ±1 |
ISA/ANSI |
| E |
Cr / Const |
-50 to 800 |
1 |
777 ±1 |
ISA/ANSI |
| S |
Pt / Pt-Rh(10%) |
0 to 1700 |
1 |
1555 ±1 |
ISA/ANSI |
| R |
Pt / Pt-Rh(13%) |
0 to 1700 |
1 |
1666 ±1 |
ISA/ANSI |
| B |
Pt-Rh(6%) / Pt-Rh(30%) |
400 to 1800 |
1 |
1777 ±1 |
ISA/ANSI |
Standard Options
Any fo the Individual standards as below for each T/C in the ordered option
| Option N |
ISA/ANSI Standard |
Option D |
DIN Standard |
| Option I |
Indian Standard |
Option J |
Japanese Standard |
| Option B |
British Standard |
Option R |
Russian Standard |
I/O Options
| YV(YV=JN Etc) |
: |
Simulation of Millivolts & a Single T/CJ or K or T or E or R or S Etc |
| XX |
: |
Simulation of Millivolts & T/Cs JN, KN, TN as per above Table |
| YY |
: |
Simulation of Millivolts & T/Cs RN, SN, BN as per above Table |
| UN |
: |
Simulation of Millivolts & T/Cs JN, KN, RN as per above Table |
| VN |
: |
Simulation of Millivolts & T/Cs JN, KN, SN as per above Table |
| WN |
: |
Simulation of Millivolts & T/Cs JN, KN, BN as per above Table |
| GG |
: |
Simulation of Millivolts & any three (To be Specified) T/Cs as per above Table This is a custom combination whichmust be completely specified by the user. |
| CJ Compensation |
: |
Automatic or Manual |
| Output Impedance |
: |
< 0.05 ohm |
INPUT SPECIFICATIONS
The 28543 measures mV & T/C signals with following specifications
| Millivolts |
: |
80 mV with resolution of 0.02 mV |
| Optional T/Cs |
: |
Combinations of 3 T/Cs ordered as per above Table for output |
| I/P Impedance |
: |
> 1 Megohm for mV & T/C input |
| I/P Protection |
: |
Input/Output Terminals are protected for 24V DC |
INDICATOR SPECIFICATIONS
Display
4 Digit 7 - segment 8mm LCD
INSTRUMENT ACCURACY
Accuracy at operating temperature between 22-32 °C, valid within a one year Calibration Cycle
| Basic Accuracy |
: |
±0.05% of rdg ±0.05% of f.s. ±1dgt |
| CJ Error |
: |
1°C for Ambient Temperature of 5-55 °C |
| Lead-Error |
: |
1 °C for lead resistance of 100ohm per lead |
| Self-Check |
: |
Displays 66.66 ±2 for mV & a figure for T/Cs as per above Table |
POWER SUPPLY SPECIFICATIONS
Power Supply Options
| Option A |
: |
7 Nos of AA size dry cells giving 10.5V |
| Option B |
: |
7 Nos of Ni-Cd AA size Rechargeable cells giving 8.4V |
Battery Life
| Dry Cells |
: |
12 to 16 Hrs of continuous use |
| Ni-Cd Cells |
: |
10 to 12 Hrs of continuous use |
Low Battery
Indicated by lighting all decimals or "LO BAT" indicator
Mains Operation
A connector is provided for a battery eliminator
ENVIRONMENTAL SPECIFICATIONS
| Rated Temp |
: |
5 to 55 °C |
| Humidity |
: |
Less than 90% RH ( Non-Condensing ) |
| Zero Drift |
: |
Less than 1dgt for every 10°C beyond the specified ambient of 22 - 32 °C |
| Span Drift |
: |
Less than 0.0015% of rdg / °C |
| Storage Temp |
: |
0 to 70 °C (Without Batteries & Accessories) |
MECHANICAL SPECIFICATIONS
| Enclosure Size |
: |
125(W) x 200(H) x 60(D) mm |
| Enclosure Finish |
: |
Powder coated |
| Enclosure Weight |
: |
1.0 Kg (Without Batteries) |
STANDARD ACCESSORIES
Battery Eliminator, Probe Set, Leather Case, Wooden Case, Instruction Manual, Warranty Certificate, Calibration Certificate Traceable to NPL.
Charger for Ni-Cd Cells if Power Supply Option B is selected.
ORDERING INFORMATION
While ordering please specify the various options as per the following ordering code
| Model No. |
Sensor Option Code |
Standrds Option Code |
P.S. Option Code |
| 28543 |
X |
X |
X |
Example
Specify 28543GGA (GG = RD, KN, BD) to order the T/C Simulator with 8mm LCD display for simulating 80mV and T/Cs R in DIN Std, K in ANSI Std and B in DIN Std with individual ranges of 0 to 1700° for R, -50 to 1360°C for K and 0 -1700° for S, operating on 7 Nos of AA size dry cells. |
