EWS-DL data logger stores calibration setpoint data and up to 4 days of operating data for 60 internal values every minute. With the EWS-DV data viewer program, a graph of operating current can be seen that will show cycle time, running current, starting current, process or product temperature, and alarm setpoints, This is a very valuable tool for HVAC&R technicians to maintain and troubleshoot a system. The EWS-DL can be plugged into and removed from the EWS-MP while still in service, or the stored data can be downloaded to a laptop computer on site while the EWS-MP is in operation. The data is stored in non-volatile memory so the logger can be disconnected and sent to a remote site for analysis without loss of data. The logger over-writes the oldest data and keeps the most current 4 days of information.