The AC charger supplied with the calibrator is only sufficient to charge the LI-Ion batteries. If you want to run the unit from AC, whilst taking measurements, a stronger bench power supply is required (e.g. 12V, 1Amp). This power supply should be of a good quality with a small AC ripple.
Environmental
Humidity : 0 to 85% (non-condensing)
Environmental
Operating Temperature : 0°C to 50°C
Environmental
Storage Temperature : -40°C to 60°C (including battery)
Physical
Size : 149 x 34 x 77mm without rubber boot, 155 x 43 x 85 with rubber boot