What is the maximum voltage and current this meter can safely measure?

The Cen-Tech 61593 can measure up to 1000 VDC or 700 VAC (sine wave). For current measurements, the maximum safe level is 20 amperes continuous, or 20 amperes for 15 seconds maximum on the 20A setting. Do not test voltage on circuits higher than 750 volts AC or 1000 volts DC, or current higher than 20 mA on circuits with higher amperage.