Flintec FT-10xx - Manual (Page 14)

FT-10 Smart Process Indicator, Technical Manual, Rev. 1.0, January 2014
4.3.1 Power Supply Connection and Grounding
Power supply voltage of the instrument shall be between 12 VDC and 28 VDC. The pin configuration of the
24 VDC power supply connector located right - bottom of the instrument is shown in Figure 4.1 below.
The pin layout of the 24 VDC
connector of FT-10 Series
( rear view )
0V 24V
Figure 4.1 - The pin layout of 24VDC connector
The quality of the instrument’s ground will determine the accuracy and the safety of your measuring system.
A proper ground connection is needed to minimize extraneous electrical noise effects on the measurement.
A poor ground can result in an unsafe and unstable operation. It is important that the instrument should not
share power lines with noise-generating parts such as heavy load switching relays, motor control equipment,
inductive loads, etc. If the condition of the power line in the plant is poor, prepare a special power line and
grounding.
Before interfering the instrument, turn off the power and wait at least for 30 seconds.
Warning: Connect the Shield pin to the reference ground.
4.3.2 Load Cell Connection
To avoid damages, the load cell wiring should be made carefully before energizing the instrument. Load cell
connection detail is shown in Figure 4.2
In 4-wire installations the sense and excitation pins with the same polarity should be short circuited at the
connector side. If you have junction box, use 6 wire cable between FT-10 and the junction box, and short
circuit these pins at junction box for better performance.
4 wire LC connection
6 wire LC connection
Figure 4.2 - Load cell connections
Warning: Always connect Sense pins to Excitation pins for 4 wire connection. Non-connected sense pins
may cause the wrong Excitation voltage measurement and create an accuracy problem.
Warning: Connect the load cell cable shield to the reference ground or shield pin of the load cell
connector.