CL543B Thermocouple, Millivolt and RTD Calibrator and Thermometer
Calibrator for Thermocouple and RTDs (PT100)
Supported Applications
The Omega CL543B is a handheld thermocouple and RTD calibrator designed for high-accuracy automated temperature calibration in plant, field, or shop environments. The device supports heat treating surveys, accuracy tests, and troubleshooting of RTD sensors with automatic detection of 2-, 3-, or 4-wire connections.
It is capable of verifying resistance, cold junction temperature, and output signals for a wide range of sensor types:
• Thermocouples: Types J, K, T, E, R, S, B, N, G (W), C (W5), D (W3), P, L (J-DIN), and U (U-DIN).
• RTDs: Pt 10Ω, 50Ω, 100Ω, 200Ω, 500Ω, 1000Ω; Cu 10Ω, 50Ω; and Ni 120Ω.
The CL543B meets or exceeds the requirements of AMS 2750 as both a secondary standard instrument and a field test instrument. It includes NIST certification (no points).
Operating Conditions & Performance
The series operates within an ambient temperature range of -20 to 60°C (-4 to 140°F). Storage is supported from -30 to 60°C (-22 to 140°F). Humidity limits are defined as 10% ≤ RH ≤ 90% (non-condensing) at 0 to 35°C, and 10% ≤ RH ≤ 70% (non-condensing) at 35 to 60°C.
Performance specifications vary by sensor type and range. General accuracy is stated as ±(0.008% of reading + 0.006 mV) for thermocouples and voltage, and ±(0.015% of reading + 0.05Ω) for 3- and 4-wire RTDs.
Specific accuracy values are defined by temperature ranges in the specification tables:
• Type J Thermocouple: Accuracy varies from ±0.25°C (-200 to -150°C) down to ±0.13°C (-50 to 300°C), and up to ±0.20°C (850 to 1200°C).
• Type K Thermocouple: Accuracy ranges from ±0.70°C at -230 to -100°C, improving to ±0.19°C between -100 and 600°C.
• Pt 100Ω RTD (DIN/IEC/JIS): Accuracy is ±0.13°C from -200 to -150°C, ±0.24°C from -150 to 360°C, and increases with temperature up to ±0.37°C at 740 to 850°C.
The cold junction sensor is accurate to ±0.05°C. Measurement ranges span -200.00 to 2320.00 °C (-328.00 to 4208.00 °F) for temperature, and 0.00 to 4010.00 Ω for resistance.
Configuration Options
The CL543B features a rugged design with a rubber boot enclosure, low-profile switches, brass screws, and an integrated kick stand for bench use. The display includes backlighting for operation in dark areas.
Connections:
• Banana jacks (1+ and 2-) mounted on the top end of the housing; these are not temperature compensated and intended only for millivolt signals.
• Screw terminal block for thermocouple wire connections.
• Miniature thermocouple socket with an isothermal block.
Power Supply:
• Battery: Four 'AA' alkaline 1.5V (LR6) batteries included.
• Optional NiMH rechargeable battery kit available, including a 120 Vac charger, four NiMH batteries, and AC/DC cords.
Included Accessories:
• Rubber boot (integrated).
• NIST Cert (no points).
• Operator's manual.
Key Product Differences
The series is represented by the single model CL543B, described as a "Thermocouple and RTD temperature calibrator." The device supports multiple thermocouple materials including Iron-Constantan (J), Chromel-Alumel (K), Copper-Constantan (T), Platinum-Rhodium alloys (R, S, B), Tungsten-Re (G, C, D), and Palladium-Gold-Palladium (P).
RTD support includes various alpha coefficients: 1.385 for DIN/IEC/JIS standards; 1.390 for Burns curves; 1.392 for Old JIS 1981; and 1.393 for US Lab specifications.
Optional accessories available separately include a deluxe hands-free carrying case, mV/V test leads (red/black with banana plugs and alligator clips), an RTD wire kit, and red/black leads with spade lugs.
| Additional Features 1 | Read and Source Signals |
| Alerts | Red LED displays OVERLOAD or out of range conditions |
| Battery Life | 50 hr, low battery warning with less than 1 hr operation left |
| Cold Junction Sensor | ≤± 0.01% °/ ° from ambient temperature ( °C or °F) |
| Display Type | LCD |
| Display Type Note | High contrast graphic Liquid Crystal Display. LED backlighting for use in low lit areas. |
| Height | 41 mm |
| Length | 143 mm |
| Operating Temperature, Min | -20 °C |
| Over-Voltage Protection | Up to 60 vrms (rated for 30 seconds), protection against misconnection |
| Relative Humidity, Max | 0.9 |
| Relative Humidity, Min | 10% |
| Relative Humidity Note | 10% ≤RH ≤90% (0 to 35°C),non-condensing; 10% ≤RH ≤70% (35 to 60°C),non-condensing |
| RTD And OHMS Read | Resistance Ranges: 400Ω Range: 0.00 to 401.00 and 0.000 to 401.000 4000Ω Range: 0.0 to 4010.0 and 0.00 to 4010.00 Accuracy: ± (0.015% of reading + 0.05Ω) Excitation Current: 0.9 mA to 401Ω, 0.4 mA to 4010Ω (nominal) |
| RTD And OHMS Source | 3- and 4-Wire Accuracy: From 1 to 10.2 mA External Excitation Current: ± (0.015% of setting + 0.05Ω) Below 1 mA of External Excitation Current: Add (0.025 mV/mA excitation current) 2-Wire Accuracy: Add 0.1Ω to 3-wire and 4-wire accuracy Resistance Ranges: 400Ω Range: 0.00 to 401.00 and 0.000 to 401.000 4000Ω Range: 0.0 to 4010.0 and 0.00 to 4010.00 RMS Noise: 400Ω Range: ≤± 0.005Ω from 0.1 to 10 Hz 4000Ω Range: ≤± 0.05Ω from 0.1 to 10 Hz Allowable Excitation Current Range: 400Ω Range: 10.2 mA max; steady or pulsed/intermittent 4000Ω Range: 1 mA max; steady or pulsed/intermittent Pulsed Excitation Current Compatibility: DC to 0.01 second pulse width, 0.025 mV, mA excitation current |
| Series ID | CL543B-series |
| Storage Temperature, Max | 60 °C |
| Storage Temperature, Min | -30 °C |
| Supply Voltage | 6 Vdc |
| Temperature Effect | ≤± 25 ppm/°C |
| Thermocouple Type | J, K, T, E, N, R, S, U, B, G, C, D, L, P |
| Voltage Read | Ranges and Resolution: -13.000 to 80.000 mV and -13.0000 to 80.0000 mV Accuracy: ± (0.008% of reading + 0.006 mV) Input resistance: ≥10 MΩ Normal Mode Rejection: 50/60 Hz,50 dB Common Mode Rejection: 50/60 Hz,120 dB |
| Voltage Source | Ranges and Resolution: -13.000 to 80.000 mV and -13.0000 to 80.0000 mV Accuracy: ± (0.008% of setting + 0.006 mV) Source Current: ≥10 mA Output Impedance: <0.3Ω RMS Noise: ≤± 0.0005 mV from 0.1 to 10 Hz Short Circuit Duration: Infinite |
| Weight | 0.34 kg |
| Weight Note | 0.34 kg (12.1 oz) with boot and batteries |
| Width | 76 mm |