pH is the potential measure of hydrogen ion concentration in
the solution, expressing the acidity or alkalinity of solution on a
Logarithmic scale on which 7 is neutral, lower values are more acid
and higher values are more alkaline.
SANSEL make online ph 641 indicator is a precise, rugged and weather
proof instrument carefully designed for the most accurate
measurement of pH/ ORP in all industries. This instrument is a panel
mountable with a compact standard size of 48 x 96 x 65mm with front
end pot meter type easy adjustable 4pH & 7pH buffer calibration, zero
& SPAN adjustment for ORP. This instrument operates from 90V to
270V AC / DC ,50Hz.