Built to a British meteorological office specification, the speed indicator is housed in circular moulded bakelite case and a dual positionable flange allows for it to be flush panel or wall-mounting. These dial indicators may be remotely sited, with up to six units incorporated in a circuit. Wind speeds can, therefore, be displayed at key vantage points suck as in the crane cab for the benefit of the operator, at the base of the crane for information before operation and in the office of the safety representative.
The dial is scaled over 270° and can be calibrated in MPH, KNOTS, M/S or KM/HR. a central set screw allows the pointer to be set on zero. The indicator accepts the voltage signal from the anemometer and the voltmeter movement within the case drives the pointer. Calibration is factory set during manufacture. This should not be reset by operators.