Braking Chopper; Low Voltage Mode - ABB ACSM1 Firmware Manual

Automatic identification of the supply voltage is performed every time the drive is
powered. Automatic identification can be disabled by parameter
SUPPLVOLTAUTO-ID; the user can define the voltage manually at parameter
SUPPLY VOLTAGE.
The intermediate DC circuit is charged over an internal resistor which is bypassed
when the capacitors are considered charged and the voltage has stabilized.

Braking chopper

The built-in braking chopper of the drive can be used to handle the energy generated
by a decelerating motor.
When the braking chopper is enabled and a resistor connected, the chopper will start
conducting when the DC link voltage of the drive reaches U
maximum braking power is achieved at U
U = 1.35 × 1.25 ×
DC_BR

Low voltage mode

A Low voltage mode is available to extend the supply voltage range. When the mode
is enabled, the drive can operate below the nominal range, for example when it
needs to be powered from an emergency supply.
Low voltage mode can be activated by parameter
voltage mode introduces parameters
VOLT DC MAX
respectively. The following rules apply:
• 47.06 LOW VOLT DC MIN
• 47.07 LOW VOLT DC MAX
• 47.07 LOW VOLT DC MAX
U = 1.35 ×
DC
U , high = 1.25 × U
DC
U , low = 0.8 × U
DC
1.19 USED SUPPLY
for adjustment of minimum and maximum DC voltage control levels
= 250 to 450 V
= 350 to 810 V
> 47.06 LOW VOLT DC MIN
Overvoltage fault level (U
Overvoltage control level (1.25 × U
1.07 DC-VOLTAGE
Undervoltage control level (0.8 × U
Undervoltage trip level (U
1.19 USED SUPPLY VOLT
DC
DC
+ 30 V.
DC_BR
VOLT.
47.05 LOW VOLT MOD
47.06 LOW VOLT DC MIN
47.03
47.04
, high + 70 V; 880 V max.)
DC
; 810 V max.)
DC
; 400 V min.)
DC
, low - 50 V; 350 V min.)
DC
- 30 V. The
DC_BR
ENA. Low
and 47.07 LOW
+ 50 V.
Drive control and features
45