DPM-3 Transducer Techniques Digital Panel Mount Meter

The Transducer Techniques DPM-3 Digital Panel Mount Meter is a versatile, cost-effective solution to a wide variety of monitoring and control applications. The Transducer Techniques DPM-3 Digital Panel Mount Meter are easily set up to produce an accurate display of weight, load or direct reading of microvolts. Setup can be via front panel pushbuttons or the meter's serial interface. Digital scaling of zero and span provides direct readout in engineering units. Digital calibration of all ranges eliminates drift associated with potentiometers found in non-microcomputer-based meters. Selective security lockout of the front panel keys protects against accidental changes to the meter setup.

A unique method of analog-to-digital conversion provides 60 conversions per second (50 for 50 Hz operation), while integrating the signal over a full line cycle for maximum noise rejection. Self-calibration cycles reduce the average reading rate to 56 per second (47 for 50 Hz). This fast read rate provides an accurate display of peak signal input and quick response in control applications.

An adaptive auto-filter automatically selects a time constant appropriate for the encountered signal noise level. This ensures stable displayed readings and outputs while responding rapidly to changes of the input signal that exceed a selected threshold value. Input signal polarity may be selected as normal or reverse.

The NEMA-4 (IP65) 1/8 DIN case is made of high impact 94V-0 UL-rated plastic. Mounting is from the front of the panel and requires less than 110 mm behind the panel. All wiring is by removable plugs conforming to UL61010C safety standards. All output options are isolated from meter and power ground by 250 VAC minimum.

Alarm or setpoint control is provided by an optional relay board with two or four Form C 8A mechanical relays or two or four Form A 120 mA solid state relays. The setpoints may be latching or non-latching, be energized above or below the setpoint, or operate in a fail-safe mode. The relays can operate from the filtered signal to reduce relay chatter or from the unfiltered signal for fastest response. Snubber circuits and a programmable relay switching time delay extend relay contact life.

An isolated analog output of 4-20 mA, 0-20 mA, 0-10V or -10 to +10V can be provided by an optional analog output board. The output is linearized to the display and can operate from the filtered or unfiltered signal input. It can be scaled via front panel pushbuttons or the meter's serial interface.

Optional RS232, RS485, or USB serial interfaces allow the DPM-3 to communicate bidirectionally with computers, PLC's or other digital devices. An optional USB-to-RS485 converter board allows a primary DPM-3 to be interfaced to a computer and to be the device server for a network of up to 31 other DPM-3's on an RS485 bus, while itself retaining all capabilities of a meter.