ABB DCS 500B Description

Also see for DCS 500B: Operating instructions Service manual Service manual

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ABB DCS 500B Description Manual pdf 70 page image

Functional Software description62 DCS 500 Software DescriptionSPEED SCALING (2103) Max. speed of drive in 0.1 rpm. Thisrpm value equals to spped reference value of 20000.FIELD WEAK POINT (1012)Motor field weakening point. Scaling in speed units.Example. The motor is labeled 1500 - 1800 rpm, 440VSet SPEED SCALING (2103) = 18000Set FIELD WEAK POINT (1012) = 16666 (=1500 * 20000 / 1800 )FLUX referencehandlingThe FLUX reference can be selected by input [FLUX REF SEL](1004) as follows: The constant 100% flux reference (= 4096 unitsin software) is selected if input [FLUX REF SEL] (1004) has value0. Value 1 selects the flux reference from input [FLUX REF] (1002),which is connected to the application program (by means of func-tion blocks in DCS 500B), when there are special requirementsfrom the process point of view.When the motor FLUX is reduced, a larger amount of armature cur-rent is needed to create the same torque on the motor shaft. Thiscan be used on some applications, e.g. unwinder section in awinder. Because of a bigger armature current, the resolution of themeasurement is better, which helps to control small torques withgood accuracy.Normally the FLUX reference is not changed rapidly. For example,on unwinder the FLUX reference follows the diameter of the roll.Flux Reference inEmergency StopThe control range for FLUX is 1:5, so the minimum FLUX referenceis 20% of nominal. In case of EMERGENCY STOP, the reducedFLUX reference is changed to maximum possible FLUX referencedefined by the field weakening area.EMF referencehandlingThe EMF reference is selected by input [EMF REF SEL] (1005).Value 1 selects the EMF-reference from input [EMF REF] (1003) ,which is connected to the application program. Value 0 selects pa-rameter LOCAL EMF REF (1006) as the EMF reference.The scaling of LOCAL EMF REF (1006) is:100% = U MOTN VPI - controller PI-controller is needed to correct inaccuracies caused by the proc-ess, e.g. network AC voltage variations.I-part of the controller is reset below a certain EMF-level becausethe rotor resistance value IR would otherwise cause an