Delta control engineering corporation supplies microcontroller-based line parameters indicator for v/hz. The technical specifications of the mains line parameters indicator from delta control engineering corporation are: panel cut-out size is 92 mm x 46 mm. Line frequency is up to 99.9hz, with resolution/accuracy of ±0.1 hz; resolution of 1 v is obtained in the voltage indicator. Accuracy of class 0.5 is also obtained in the voltage indicator. The supply voltage ranges from 180 v to 260 v. The displays are 10 mm leds. It has selector for external voltage input or line voltage readout. A range of 0 to 500 v is available with the application of an external voltage. Applications of mains line parameters indicator from delta control engineering corporation range from servo-stabilizers to test equipment, stand-alone indicators in factories to switchboards.