apcupsd sc420i line voltage

[Vukovics Mihály <vm@informatik.hu>]

Hello Community,

I am strugling with APC SmartUPS SC420I and apcupsd.
The UPS is connected via usb-to serial adapter and 940-0024E cable.

The UPS is recognized as "Back-UPS Pro 280" instead of SC420I and the 
line voltage is displayed as 120V instead of the real 230V.

UPSTYPE apcsmart
DEVICE /dev/ttyUSB0

Has any of  you experienced like this and know how to fix at least the 
line voltage value?

Br,
Mihaly