Extech recently announced today the launch of the MM750W, a CAT-IV True RMS digital multimeter that HVAC and Refrigeration professionals can use to view electrical and temperature readings and datalog remotely using the ExView® W-Series app on smartphones and tablets.

Why App-Based Diagnostics Makes a Difference
The innovative new meter uses a Bluetooth® module for wireless connectivity to iOS® and Android™ devices. The MM750W transmits real-time data for monitoring, trending, reporting and analysis. For HVAC/R installation and maintenance work, technicians can monitor and datalog readings at a safe distance from energized equipment, moving components and other hazardous locations (up to 10m/33ft). When extended temperature readings are needed, the DMM and Type-K temperature probe can be placed at the point of measurement (duct work, suction/liquid lines, air handler) while a tech monitors it remotely. Plus, the new digital multimeter (DMM) makes it easier to perform remote tasks such as powering up circuits, compressors, chillers and pumps or calling for heat/cooling at a thermostat, controller, or building automation system that is not nearby the device under test.

Expanded Mobile Versatility
From a time-saving perspective, the MM750W lets HVAC/R technicians datalog readings throughout a site while easily viewing readings on an iPhone®, iPad® or Android device with a large, easy-to-read numerical readout and analog-style bar-graph. The datalogging sample rate can be adjusted according to a job’s requirements using the app and up to 15,000 datalogged readings can be stored.

To simplify reporting, electrical and temperature readings can be easily exported to an Excel® file to send to customers, managers or colleagues using your device’s email app. High and low alarms can be set on the app to alert the user of abnormal conditions, such as insufficient heating or cooling, or unusually high loads on a compressor nearing failure. The app’s camera mode allows photo-documenting of a job site and testing conditions, complete with a date and timestamp and current reading value. Photos simplify record-keeping at large sites by clearly recording where readings were taken, avoiding confusion and costly errors.

Full-Function HVAC/R Multimeter
The ruggedized Extech is a no-compromise 14-function True RMS DMM that reads AC/DC voltage and current (both A and μA), resistance, capacitance, frequency, duty cycle (dwell), continuity, diode testing (3.0V), and ambient temperature (using its Type K thermocouple bead probe). The meter’s micro amp (μA) function is designed to quickly test a flame sensor and identify troublesome issues such as a dirty sensor, flame lifting or carbonizing—often resulting in the control board locking out the furnace. Technicians can use the built-in non-contact voltage (NCV) detector to quickly scan for energized circuits in a work area--without additional tools--before starting work. For non-invasive current load testing of compressors and other equipment, an optional clamp adaptor turns the DMM into a virtual clamp meter with higher current ranges.

The new meter ensures precise readings with 0.6% accuracy and it is rated to Category IV overvoltage (CAT IV-600V, CAT III-1000V). Several statistical data functions include minimum/maximum, difference (MAX-MIN), relative mode to zero the meter, and data hold to freeze the display reading. Auto-power-off protects battery life but can be disabled when extended testing is needed, such as datalogging.

The Extech MM750W includes test leads, Bluetooth wireless datalogging module (DAT12), Type-K temperature probe, 9V battery and carrying case. To learn more about the new meter,