ABB ACS310, Быстрый старт

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Quickstart Guide
ABB PLC and drives integration using Modbus RTU
Modbus RTU ‐ 9 ‐ PLC and drives integration
Bus line
Construction 2 cores, twisted, with common shield
Conductor cross section >0.22 mm
2
(24 AWG)
‐ recommendation 0.5 mm
2
corresponds to Ø0.8 mm
Twisting rate <10/meter (symmetrically twisted)
Core insulation Polyethylene (PE)
Resistance per core <100 Ω /km
Characteristic impedance Appr. 120 Ω (100…150 Ω )
Capacitance between the cores <55 nF/km (if higher, then max bus length
must be reduced)
Terminating resistors 120 Ω , ¼ W at both line ends
Remarks Cables with PVC core insulation and a core
diameter of 0.8 mm can be used up to a
length of appr. 250 m. In this case, the bus
terminating resistor is appr. 100 Ω .
ABB cable TK505
For an easy Modbus installation in the CPU end, the pre ‐ made ABB cable TK505 can be used. It includes a 9 pole D ‐
sub contact with built ‐ in end termination (120 Ω ) and pull ‐ up/pull ‐ down resistors (2*270 Ω ). This contact is
suitable for AC500 ‐ eCo COM1. It can also be used for AC500 COM2 (even though another voltage level is used),
but only if the GND wire is not connected to the Modbus slaves (2 ‐ wire solution, preferred for AC500 COM ports).