Lascar usb data logger 4 20ma current loop lascar el usb 4 p buy lascar usb data logger 4 to 20 ma el usb 4 ndash a high quality current loop data logger that can measure and store up to 32 000 readings over a 4 to 20ma dc measurement range p the unit is simply plugged into the usb port of a pc to download the data using the included purpose designed software the data logger may be set up by changing the logger name logging rate high and low alarms and start date and time also th