Eurotherm Action Instruments - Q520 - Thermocouple Input Two-wire Transmitter

Q520
Thermocouple Input, Isolating Two-wire Transmitter

TECHNICAL SPECIFICATION (Q520)
Input		Types: Accepts two J, K or T Type thermocouples
	Ranges:	see Table 1
Burnout Detection		Upscale standard; Downscale, option B
Cold-Junction Compensation Error		1°C typical, 0 to 80°C ambient; 3°C typical, -40 to 0°C ambient
Output Range		4-20mA
Supply Voltage Range		12 to 35VDC, each channel
Output Accuracy		< 0.1% of full-scale input (mV) typical, < 0.2% maximum @23°C including linearity, repeatability and hysteresis (not including CJC error)
Adjustability		Front accessed 10 turn, + 5% of span for zero and span
Stability		< 0.025%/°C of full-scale maximum for full-scale and zero
ESD Susceptibility		Capable of meeting IEC 801-2 level 2 (4kV)
Isolation		1800VDC or peak AC between input and output and to channel
Response Time		100mSec typical (10 to 90%)
Temperature	Operating:	-40 to 80°C (-40 to 176°F)
	Storage:	-40 to 80°C (-40 to 176°F)
Humidity (non-condensing)
	Operating:	15 to 90% (@45°C)
Wire Terminal		Socketed screw terminals for 12-22 AWG
Weight		0.34 lbs
Agency Approvals		CSA certified per standard C22.2 (File No. LR42272).
		UL recognized per standard UL508 (File No. E99775).
		CE conformance per EMC directive 89/336/EEC and low voltage 73/23/EEC (Input <75VDC).

Operation
The ActionI/Q model Q520 operates as a two-wire transmitter; each channel derives its power from a (12-35VDC) source connected in series with the 4-20mA output loop. Typically a 24VDC source is used for power, allowing 12VDC (600W @ 20mA) for other devices connected in series, in the current loop. The outputs of the Q520 are isolated from the inputs and protected from reverse polarity. Zero and span pots are provided for each channel.

The Q520 provides a dual (2) channel, thermocouple to current, isolating, two-wire transmitter in one package. Standard input temperature ranges (see Table 1) are calibrated to rated accuracy. One range per module; two channels per module.

Note: The voltage source (Vs) connnected to the output must be sufficient to accommodate all other device loads (RL) in the current loop. Vs>12V+0.02xRL

Calibration

Connect the input to a calibrated thermocouple simulator or millivolt source ( thermocouple wire corresponding to the input range may be required; check your calibrator's capabilities). Connect the output in series to a voltage source capable of supplying at least 20mA and a milliamp current meter.
Set the calibrator to the specified minimum temperature or equivalent millivolt value and adjust the zero potentiometer for 4mA output.
Set the calibrator to the specified maximum temperature or equivalent millivolt value and adjust the span potentiometer for 20mA output.
Repeat steps 2 and 3, as necessary, to validate calibration. Output is linear to mV, not temperature.

Last Updated Thursday, July 28, 2005

Q520Thermocouple Input, Isolating Two-wire Transmitter

Q520
Thermocouple Input, Isolating Two-wire Transmitter