FT-111(D) Panel Weighing Indicator, Technical Manual, Rev.1.0.0, May 2019
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4 I
NSTALLATION
PRECAUTION
: Read this section carefully before installation of the instrument. Applying the
recommendations in this section will increase your system reliability and its long-term performance.
4.1 Recommendations
Environment
The weighing indicator should be placed in an area which is clean, not getting direct sun light if possible, having a
temperature between -15 ºC and +55 ºC and humidity not exceeding 80% non-condensing. All external cables should be
installed safely to avoid mechanical damages.
This instrument is very low level signal measuring instrument. To avoid electrical noise, it should be separated from
equipment that produce electrical noise. The instrument body must be connected to the good ground against the
electromagnetic disturbances. Load cell cable must be separated from other cables especially from power cables if possible.
If there are electrical noise-generating equipment such as heavy load switches, motor control equipment, inductive loads
etc., please pay attention to the EMC interference and take all the prevention. Connect parallel reverse diodes to the DC
inductive loads like relays, solenoids etc. to minimize voltage peaks on the DC power lines.
Cabling
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All cables coming to the instrument shall be high quality and shielded.
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Distance from load cell cables, interface cables and DC power supply cables to power line cables shall be
minimum 30 cm. The separate cable tray usage for these low signal level cables is strongly recommended.
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Shields of all cables should be connected to the grounding screws under terminals as shown at the picture below.
Figure 4.1
– The shield connection to the protective earth.
Electrical Connection
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Always remember that FT-111 terminal is very low voltage measuring instrument used in the industrial
environment. Your proper installation increases reliability and performance of the instrument.
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Only the trained person should interface the instrument against malfunction at installation.
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If the energy condition of your plant is not good enough, prepare a special power line for DC power
supply in the cabinet.
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The quality of your plant grounding will provide weighing accuracy and the safety of FT-111. If
grounding of your plant is not good enough, prepare a special grounding.
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Power off the instrument before connecting or disconnecting any peripheral instrument.
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The shielded cable usage and ground connectio
n of the cables’ shields will increase the immunity of
FT-111 against electrical disturbances.
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All required electrical connections should be done as described in the installation section.
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If you have to service the terminal, turn the power off and wait at least 30 seconds before opening
housing.
