PT610, PT620, PT630
Instruction Manual
9
4 INSTALLATION
4.1 GENERAL RULES
Warning:
Please read this manual carefully before installing the instrument. Applying the
recommendations in this section will increase your system reliability and long term performance.
Positioning
The indicator should be placed in a clean area, out of direct sun light if possible, with a temperature
between -15 ºC and +55 ºC and humidity not exceeding 85%RH, non-condensing. All external cables
should be installed securely to avoid mechanical damage.
The instruments are very low level signal measuring instruments. To avoid electrical noise they should
be separated from any equipment that produces electrical noise.
•
Load cell cable trays must be separated from others, if possible, as power or motor control
cables can cause interference.
•
If there is noise-generating equipment, such as heavy load switches, motor control equipment,
inductive loads etc., please take care to protect against EMC interference or install them well
separated or in a separate section well away from that equipment.
•
Connect parallel reverse diodes to the DC inductive loads like relays, solenoids etc. to minimize
voltage peaks on the DC power supply.
•
If the condition of your plant electrical supply fluctuates or is subject to noise and interference,
prepare a special power line and grounding or use a power conditioner, such as a filtering UPS.
•
Good quality grounding of the instruments will improve weighing accuracy and the safety of
your indicator.
Cabling
All cables coming into the indicator case should be shielded. The shield can be grounded to the internal
earth connection for the case. Please use separate cable trays for these low signal level cables. The
distance from load cell cables, interface cables and DC power supply cables to mains power line cables
must be minimum 50 cm unless they are installed in a properly grounded steel conduit or you could
experience a reduction in performance.
Warning:
Please always remember that PT610, PT620 and PT630 instruments are very low voltage
measuring instruments. Proper installation increases reliability and performance of the instrument.
Please do not forget that the instrument must be powered off before inserting or removing any
connector or option.
4.1.1 INSTALLATION STEPS
The same general steps apply to setting up all scales.
1. Mechanical installation. Install the indicator and load cells.
2. Connect the load cells to the indicator. When more than 1 load cell is in the scale the load cells
are usually connected together through a junction box. The junction box then connects to the
indicator. A junction box is not essential and the load cells can be connected together inside the
indicator but a junction box allows adjustment of the load cells to compensate for off-centre
loading.
3. Connect the power supply to the indicator.
4. Configure the weighing parameters of the indicator, scale capacity and division as a minimum.
5. Configure any communications parameters.
6. Calibrate the indicator so the correct weight is shown for a load on the scale.
7. If corner adjustment is required, match corners and recalibrate.
8. Set any set-points or operating parameters.
9. Check the scale is working correctly.