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Isolated power supply, Catastrophic damage – Fairbanks FB2550 SERIES User Manual

Page 112

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Section 5: Input/ Output

07/2012

112

51254 Rev. 3

5.13. 4-20

M

A ANALOG CARD (

30919

)

The

4-20 mA

ANALOG CARD

is a Passive Current Loop Device with 16 Bit

High Resolution Output.

4-20mA Specifications

16 bit resolution +/- .01 integral linearity

Current Loop Voltage

Compliance

A

PASSIVE DEVICE

, as the 4-20 Analog Card is, does not supply any

current loop voltage.

Customer’s external source must furnish 7 to 40 VDC power (typical
voltage 24 VDC).

The negative (-) power of the supply MUST be isolated from chassis
ground

See important

CAUTION

box below.

A separate power supply must be furnished for each output.

Full Scale Setting

Time

8 msecs.

Output Impedance

25 Meg Ohms.

Alarm Current

3.5 to 24mA (underload/overload conditions), Offset at 25°C; +/- .1% of full
scale. Offset drift; +/- 25 ppm of full scale per degree Celsius.

Total Output Error

(20mA) at 25°C: +/- .2% of full scale max.

Total Output Drift

+/- 50 ppm of full scale per degree Celsius max.

C

A

U

T

I

O

N

Failure to have an

ISOLATED POWER SUPPLY

WILL CAUSE

CATASTROPHIC DAMAGE!

Above is an example of wiring two (2) passive
nodes with an external power supply.