3 1/2 DIGIT
(Pt 100) RTD METERS
MODEL
202A-M, -R
Models 202A-M and -R are low-cost 3 1/2 digit (±1,999
count) temperature indicators for use with platinum 100 ohm RTD's
with alpha of 0.00385. They are complete with 1 mA sensor excitation,
sensor-break detection, and platinum curve linearization. Resolution
is 1° (-M) or 0.1° (-R). Readout can be in °C or °F,
as selected by push-on jumpers. The electrical connection can be by
2, 3 or 4 wires. High accuracy is provided by positive current feedback
and matched, graded components.
STANDARD
FEATURES
Mechanical features include a bright 0.56 in (14.2 mm) display, a
screw-terminal barrier strip for signal and power, and a compact 1/8
DIN case that requires less than 4.1 in (104 mm) behind the panel.
Electrical features include jumper selection of °C or °F,
a linearized recorder output of 1 or 10 mV per degree, and 1 mA current
excitation. The current source is tied to the reference of the A/D
converter for true ratiometric operation and immunity to changes in
line voltage.
OPTIONS
Options are isolated 9-32 Vdc or 26-56 Vdc power, a PCB edge connector
for display control and output of +4.7 Vdc and 4.7 Vdc power,
and a splash-proof lens cover which meets NEMA-4 requirements.
SPECIFICATIONS
INPUT
RTD type:
100- platinum with alpha of 0.00385
Calibration: IEC 751 (IPTS-68)
Configuration: 2-, 3- or 4- wire connection
Polarity: Bipolar
Zero: Adjustable ± 20°C (±36°F)
Zero tempco: ±0.05 degree/degree (-M) ,±0.01 degree/degree
(-R)
Sensor-wire resistance tempco effect per conductor:
2-wire: 20 mdeg/ ohm /deg, up to 3.8 ohm
3-wire: 50 µdeg/ ohm /deg, up to 100 ohm
4-wire: 5.0 µdeg/ ohm /deg, up to 100 ohm
Sensor-excitation current: 1 mA
Sensor-break indication: Meter displays overrange
Overvoltage protection: 25 Vp
NOISE REJECTION
NMR, SIG HI to SIG LO: 70 dB, 50/60 Hz
CMR, ANA GND to POWER GND: 120 dB DC to 60 Hz
CMV, ANA GND to ANA GND: 1500 Vp per HV test, 354 Vp per IEC
spacing
ACCURACY
AT 25°C
Span tempco:
±0.005% R/°C on all models plus ±0.05°C/°C
for -RC from -200 to 130°C
Celsius/Fahrenheit: Jumper-selectable
Full-scale step response: 1 s
Warmup to rated accuracy: 10 min
ANALOG
OUTPUT (Linearized)
Voltage:
1 mV/deg (-M); 10 mV/deg (-R)
Calibration error: Same as given under accuracy
Current: 1 mA maximum
Source resistance: 68 ohm
ANALOG-TO-DIGITAL CONVERSION
Technique: Dual-slope, average value
Signal integration period: 100 ms
Read rate: 2.5/s
DISPLAY
Type:
7-segment, red LED
Height: 0.56 in (14.2 mm)
Symbols: 1.8.8.8
Decimal points: XXXX (-M); XXX.X (-R)
Overrange indication: Three least-significant digits blank
DIGITAL INPUTS
Level: TTL or 5 V CMOS compatible
POWER
AC voltages: 115 or 230 Vac, ±15%
AC frequency: 49 to 440 Hz
DC voltages: 9-32 Vdc, isolated to 300 Vp;
26-56 Vdc, isolated to 300 Vp
Power consumption: 3.7 W
Output voltages: +4.7 Vdc and 4.7 Vdc ±5%, 10 mA
max
ENVIRONMENTAL
Operating temperature: 0 to 60°C
Storage temperature: -40 to +85°C
Relative humidity: 95% at 40°C (non-condensing)
MECHANICAL
Dimensions: Newport DIN2A (short 1/8 DIN) case (see Mechanical
section for drawings)
Weight: 15 oz (425 g)
Case material: 94V-0 UL-rated polycarbonate
|
|
|
† All dollar amounts on this site are shown in US currency.
|
|
 |
 |
 |
 |
 |
 |
 |
 |
 |
Part Number Builder |
 |
 |
 |
 |
 |
 |
|
|
|
Option Descriptions
|
|
(1)
|
Models
|
| |
Select 202A for standard 302 for model with INFINITY® style bezel and adapter
|
(2)
|
Input Configurations
|
| |
Select -MC for -200 to +820°C (MB) -MF for -328 to 1508°F (MB) -RC for -199.9 to +199.9°C (RB) -RF for -199.9 to +199.9°F (RB)
|
(3)
|
POWER
|
| |
Select Nothing(leave field blank) for 115 Vac, 50/60 Hz ,C1 for 230 Vac, 50/60 Hz ,C3C for Isolated 9-32 Vdc ,C3E for Isolated 26-56 Vdc
|
(4)
|
ADD-ON OPTIONS
|
| |
Select Nothing(leave field blank) for Red LED display ,G for Green LEDs for display
|
(5)
|
ADD-ON OPTIONS
|
| |
Select Nothing(leave field blank) for No Options ,BL for Lens without Newport logo
|
| NOTE: All combinations may not be valid, check spec sheet for valid part numbers. |
| | | |
|
 |
 |
|
|
|
|
Back to top |
|
|