ACS800 FAQ's

All of the “common” options listed in the stand-alone drives price list are available for
the ACS800-U31 and -37 products. Additional kVA specific options are also
available, including 2nd environment and 1st environment filters for most power sizes.
Yes, a frame R6 is available in the ACS800-37 cabinet package.
ie, There is a frame R6 ACS800-U31 and a frame R6 ACS800-37 where the -U31 is
mounted in a cabinet.
The main contactor or circuit breaker is used as part of the pre-charging circuit of the
DC bus capacitors.
A complete low harmonic drive with active supply unit and LCL line filter built in
cabinet. It has the following hardware features as standard:
· UL listing. 115Vac auxiliary power supply
· Fast aR semi-conductor fuses on AC line side
· Main contactor (frames R7i-R8i) or air circuit breaker (nxR8i)
· EMC 2nd Environment, Common mode filter
· Du/dt limitation of the output voltage by chokes in parallel connected types
(nxR8i) and additionally in 690Vac types of frame R8i.
· RDCO-03 adapter for fiber optic interface
· Top entry and exit of cables with US conduit plate
· Coated boards
The type code designations for the wall-mounted type of low harmonic drive are
ACS800-31 and ACS800-U31. The ACS800-U31 is specifically designated for the
US market and includes the US conduit box with the drive and is defaulted for horse
power and 60Hz configuration.
The type code designation for the cabinet-built type of low harmonic drive is
ACS800-37. The type code designation of the drive specifically designated for the
US market includes +C129 at lower power end and +C129+H359 at high power end
in its designation. +C129 is for UL specific design and +H359 for common motor
terminal cabinet, the latter is required in frames 2xR8i ... 6xR8i.


The absolute value of the current harmonics generated by the drive is independent
of the load current, meaning that the absolute value of the harmonics is nearly the
same at no load as at nominal load. That is why the current waveform looks
distorted even when the load current is very low. This is not an issue as the harmful
effects of harmonics depend on the absolute harmonic content based on nominal
load. For example, the standards like IEEE519-1992 refer to harmonic content as a
percentage of the total load current.
No, AC line harmonics are caused my many electrical devices and are an overall
system issue, not just associated with AC drives. The goal of low harmonic AC
drives is to contribute less harmonic distortion to the overall system.
As usage of electronic and electrical equipment increases, users and utilities are
becoming more concerned about the harmful effects of harmonics. This is leading to
more stringent power quality requirements.
An LCL filter is a filter which consists of a inductor (L), a capacitor (C), and another
inductor (L) arranged in a T-section configuration. Each input phase of the ACS800-
U31 and -37 includes a symmetrical set of these components. The inductors are
series power components that carry the full current of the drive.
ABB's ultra low harmonic drive solution uses advanced harmonics mitigation
technology that does not require external filters or multi-pulse transformer. These
drives utilize an active front-end rectifier with a LCL (inductor - capacitor - inductor)
filter. The low line harmonic content of the ACS800-U31 and -37 AC drives fulfil the
strictest harmonic requirements including IEEE519-1992 at the drive's input
terminals. This makes ABB's ultra low harmonic drive a simple and compact solution
for low harmonic AC drive.