The indicator DV 177200/72 designed to display any physical quantities to be measured, e.g. rpm, speed and flow, being present as the frequency of an electrical voltage. The supply voltage required for the operation of the 3 ½-digit LED-indicator is taken from the measuring signal. Potentiometers on the rear of the unit permit any assignment of the indicating range and the input current. The decimal point can also be adjusted. The indicator can be mounted in a hazardous area, if it is connected to an intrinsically safe circuit.
The indicators DA 72-173... Ex are designed to display any physical quantities to be measured, e.g. rpm, speed and flow, being present as the frequency of an electrical voltage. This can be a sinusoidal alternating current from an active inductive sensor or an impulse transmitter or a rectangular voltage from any pulse sensor, which is approved for hazardous areas and which is supplied separately. The auxiliary power of the LCD-indicator with 4 digits is very low and therefore permits the use in a hazardous area and it can be taken from the measuring signal or it can be supplied separately. In the first case a minimum frequency and a minimum voltage is necessary. For type DA 72-1732..Ex switches on the rear side allowing the allocation of nearly any display to the input frequency.