Four-Channel Concrete Maturity Meters have internal memory for over ten months of continuous recording of half-hour readings. Datum temperature and activation energy are user programmable. One to four locations can be monitored at once, and all channels are accessed via membrane keyboard and alphanumeric display. Maturity progress can be checked directly from the meter at any time.
HM-136 is operated by included 9V lithium battery for three weeks or more. Rechargeable HM-134 has a NiCad battery and charger to more than double battery life or permit operation from 115V AC. Both meters include Type T thermocouple wire, four connectors, RS-232 cable for downloading to a PC, and a plastic carrying case.