Tachometers (200 MKII SERIESTM)

They can be ordered as mains powered versions to operate on 115V or 230V a.c., or as d.c. powered only versions to operate on 24V d.c. power supplies. However, the mains supply versions can be powered instead by a clean external 12V d.c. supply (as long as the mains supply is not used at the same time). The circuitry is protected against supply borne interference, and the 24V d.c. supply versions are reverse polarity protected, thus offering excellent noise immunity and maximum reliability on all models.