"A pH meter is a specific type of voltmeter with a very high impedance of the input channels. The high impedance is a necessary part of the equipment because of high resistance of the pH glass electrode typically used with pH meters (usually between 20 and 100 MO)." . "Qualified" . "PH ANALYSER" . "PH ANALYSER" . "RDS850634" . "An analysing instrument intended to measure and indicate and/or produce a signal which represents the measured alkalinity / acidity in a fluid or matter." . "u20683" . "2006.06.09" . .