Panel meter’s universal input display has transmitter and alarm
Extra large digits are used for the VPM3000 series of universal input displays by Acromag. The panel meters provide process current transmitter output and limit alarm relays for current, voltage or temperature inputs.
The instruments combine the digital indicator function of a panel meter with optional signal conditioning for 4.0 to 20mA transmitter output and/or alarm trip solid-state relays. The big and bright 1.2 inch (31mm) high numerals are clearly visible from far away, even in bright sunlight, says Acromag. Field-selectable inputs accept process current/voltage and temperature sensor signals including 4.0 to 20mA, ±20mA, 0 to 10V, ±10V, Pt RTDs, and most common thermocouple varieties. The units can provide power to drive a 4.0 to 20mA transmitter and other instruments. Modbus RTU serial communication is also supported.
The VPM3000 displays are easy to set up and install, claims Acromag. Units are configurable using the front-panel pushbuttons, free Windows software, or a copy function from other units. Models are available for operation from 85 to 265V AC or 12 to 36V DC power sources. AC units can provide single or dual isolated 24V DC supplies to power a 4.0 to 20mA transmitter or other instruments. A shallow 1/8 DIN enclosure with a NEMA 4X front panel is designed for ease of installation and UL/cUL listing meets the safety requirements of industrial control equipment.
In addition to converting sensor signals to a scaled 4.0 to 20mA current for retransmission to controllers or recorders, the panel meters can also perform flow computation functions. The square root function can linearise the signal from a differential pressure transmitter to display flow rate in engineering units. A low-flow cut-off feature sets a user-defined threshold that forces the display to zero for slow flow rates that often produce unsteady output from a differential pressure transmitter. There is also a pushbutton to toggles the minimum/maximum values displayed and dual relays enable a variety of alarm trip configurations for high/low, high/high, and low/low limit triggers. The relays can also be used for process on/off control and pump alternation applications.
For desktop monitoring and data acquisition applications, free software is provided which can display and log data from multiple meters on a PC.
