Catalogs >
OMEGA >
Isolated 4 to 20 mA Transmitters

Isolated 4 to 20 mA Transmitters
7Pages

Catalog excerpts

Basic Unit Thermocouples, RTD or Ohms, Millivolts, Milliamps, Volts Custom Scaling Available. Specify input signals corresponding to 4 and 20 mA ߜ Isolated to 1500 V rms ߜ Two-Wire 4 to 20 mA Operation ߜ 9-50 V Compliance ߜ Turndown Ratio to 10:1 ߜ NMV Protection to 120 Vac ߜ -40 to +85°C (-40 to 185°F) Operation ߜ Shock Resistance to 55 g ߜ IP65 Metal Case ߜ Field-Scalable Unmatched Electrical Performance Two-wire Operation Power is obtained directly from the 4 to 20 mA loop, with no need for separate power input. This simplifies field wiring and eliminates the possibility of noise pickup from power lines. Isolation to 1500 V rms (2100 Vp) This exceptionally high CMV rating from the input to the case or output eliminates the possibility of electrical ground loops between the signal source and the receiver. It also provides a high degree of protection for the receiver against electrical hazards, such as accidental contact between the signal source and an AC power line. 9 to 50 V Compliance The loop voltage driving the transmitters can be from 9 to 50 V without loss of accuracy. The exceptionally low 9 V limit allows the transmitters to be used with low loop supply voltages, and it maximises the voltage drop allowed in the current loop for intrinsic safety barriers and load resistance. For example, at the full 20 mA output of the transmitter, a 750 ohm load can be used with a 24 Vdc source and a 150 ohm load can be used with a 12 Vdc source. In either case, there will still be enough voltage left to power the transmitter, namely 9 Vdc. 10:1 Turndown Ratio Turndown ratio is defined as zero suppression divided by span. The exceptionally high 10:1 turndown ratio possible with the TX1500 Series indicates that wide zero offset can be combined with narrow signal span for closed loop control at high gain. The signal span can also be wide for control of batch operations, where a wide range of signal levels may be encountered over the entire batch cycle.

Open the catalog to page 1

High Overvoltage Protection Overvoltage of 120 Vac may be applied across the input or output leads for 1 minute in case of all models with voltage or thermocouple input. Reverse polarity of 400 Vp may be applied across the output leads indefinitely. These exceptionally high NMV overvoltage ratings provide further protection against possible electrical faults and wiring errors. Designed for Harsh Environments Extreme Operating Temperatures The operating temperature can be from -40°C to +85°C (-40°F to +185°F) while meeting published performance specifications. This allows the TX1500 Series...

Open the catalog to page 2

Zero Suppression Signal Type for 4 mA Output RTD -200 to 750°C Pt 100 -328 to 1382°1 Ohms 0 to 365 Ω Type J T/C -50 to 660°C Iron-Constantan -58 to1220°F Type K T/C -50 to 1272°C Chromel-Alumel -58 to 2322°F Type T T/C -50 to 350°C Copper-Constantan -58 to 662°F Type E T/C -50 to 900°C Chromel-Constantan -58 to1652°F Millivolts -30 to 60 mV Milliamps -30 to 60 mA Low Volts -3.5 to 6.0 V High Volts -35 to 60 V Common Specifications, All Models Signal Output Connection: 2-wire Linear Range: 4 to 20 mA Maximum Output: 35 mA Voltage Compliance: 9 to 50 Vdc Power Supply Rejection: 0.01% of...

Open the catalog to page 3

Non-Common Specifications THERMOCOUPLE INPUT MILLIAMP INPUT Model TX1505 RTD INPUT Model TX1501 Signal Source: Pt 100 RTD Span and Zero Suppression: See input table Input Resistance (Open T/C Detector Resistance): 5 MΩBias Current, Max: 50 nA NMV Across Input Leads: 120 Vac for 1 min NMR Across Input Leads: 40 dB, 50/60 Hz, 100 mV input Thermocouple Lead Resistance: For specified performance: 100 Ω Maximum: 10 kΩ Step Response, Type: 400 ms Span for 4-20 mA Output: 5 to 100 mA Zero Suppression: -30 to 60 mA Input Resistance: 1 Ω Step Response, Type: 400 ms Span for 4-20 mA Output: 100 to...

Open the catalog to page 4

Relay output Control alarm Galvanic isolation Control room TX83A or TX82B loop-powered process indicator Sensing resistor DP25 or DP41 AC-or DC-powered process indicator with relay option Loop power provided by control room Adding Digital Panel Meters to a 4-20 mA Loop One or more digital panel meters may be added to a 4-20 mA loop for local readout in percent or engineering units, without degrading the accuracy of the 4-20 mA signal. OMEGA’s TX83A and TX82B loop-powered indicators derive all operating power from the loop itself, with a maximum loop drop of 2.5 V. The use of such indicators...

Open the catalog to page 5

S Mounting Methods See Mechanical Section for mounting drawings. 1.Surface mount with four #6 rear-entry screws. Tapped holes are provided in back of case. Screws are inserted from backside of bulkhead. Snap mount into 63.5 mm (2.50") relay track. 3. Surface mount with two #8 front-entry screws. Requires optional MAT1 adapter plate. 4. Snap mount into 69.9 mm (2.75") or 76.2 mm (3.00") relay track. Requires optional MAT1 adapter plate. 5.Snap mount into DIN relay track per CENELEC standard EN 50 022. Requires optional MDT1 rail clamp. Rail mounting of TX1500 Series Transmitters Top:...

Open the catalog to page 6

Analogue output Galvanic isolation Control room Analogue output board Sensing resistor Signal source Relay output Control output board Main board with signal conditioner & excitation supply SIG HI DP41 or DP25 digital panel meter with excitation supply and output options for alarm or control Powering the 4-20 mA Loop and the Transmitter with an a DP41 Panel Meter/Controller To Order (Specify Model No.) Model No. Accessories Option Description RTD (Pt100) or ohms (default cal. 0 to 850°C) Type J thermocouple (default cal. 0 to 500°C) Type K thermocouple (default cal. 0 to 800°C) Type T...

Open the catalog to page 7