Thermo Scientific HB-S2000, User Manual

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Sarasota 2000 Ultrasonic Multipath
Flowmeter
Section 2, SYSTEM COMPONENTS, Page 2-10 Thermo Fisher Scientific
SYSTEM COMPONENTS
2.3.3.2.2 Analogue I/O
Analogue connections are normally 4-20 mA and are made to the screw terminal blocks at the
right of the rear panel. The upper block connects to I/O board 1 and the lower to I/O board 2.
Connections 1 to 6 (upper) and 15 to 20 (lower) are the analogue inputs. Connections 7 to 14
(upper) and 21 to 28 (lower) are the 4-20 mA outputs.
The table which follows shows the connections.
Analogue inputs, 4-20 mA (0-20mA) or 0-5V
The total input range is 0-20mA though analogue inputs are normally set up as 4-20 mA. On
board links LK2 and LK4 may be removed to accept 0 to 5 volts instead (Fig 6).
Each i/p has 3 connections, 18 V excitation, input and 0V.
If the external signal source supplies the power, connections are made to input (4-20 mA +)
and to 0V (4-20 mA-).
If the Sarasota 2000 flowmeter is to power the loop, connections are made to 18V (4-20 mA+)
and to Input (4-20 mA-)
Analogue outputs, 4-20 mA
Analogue outputs are always 4-20 mA.
Each o/p has 4 connections, 18V excitation, +V, -V and 0V.
If the Sarasota 2000 flowmeter is to power the loop, the output will not be isolated. A link is
made between 18V and +V and the 4-20 mA loop is between –V and 0V.
If the external device powers the loop, the output is isolated. The 4-20 mA loop is bV
and -V
Note For compliance with EMC emissions control, analogue i/o cables should be screened
and the screen connected to one of the 0V pins for each i/o card.
See the following table for connection details.