Voltcraft vc590 oled iso digital clamp meter iso calibration voltcraft vc590 oled iso the voltcraft vc 590 is an oled iso compact clamp meter with multimeter measurement functions for a secure dc and ac current measurement up to 600a the ergonomic housing is very robust and keeps the clamp meter from any damage if dropped the clamp multimeter allows one hand operation and combines standard multimeter functions with the convenient advantage of contactless current measurement a rotary