pH Electrode Amplifiers

Sensorex electrodes can be connected directly to the meter when the preamplifier is built into the circuit. Also, the cables are relatively short. 

For longer cable runs (more than 22 feet or about seven meters) or where there is significant plant electrical "noise", an external preamplifier will help provide a cleaner signal. You may even be able to obtain longer life from your pH electrodes!

When the original equipment preamplifier cannot be accessed (e.g. it may be built into a disposable electrode), a Sensorex preamplifier will be needed, regardless of the length of cable.

The S8000 platform has an optional unity gain or differential preamplifier module that can be added to any S8000 installation.

For other installations, a low cost battery powered inline preamplifiers such as our PHAMP-1 may be adequate to match up to your controller. The economical Sensorex PHAMP-1 is a battery powered in-line design. It is designed to boost the signal and lower the impedance from a pH electrode to a pH monitor, controller, or transmitter. It can be used for long cable runs of up to 1,200 feet (300 meters). Use this preamplifier when your instrument is not designed to power a remote amplifier. The PHAMP-1 can also be used to input a pH electrode signal directly into a device which can accept voltage inputs. The batteries are sealed and have an estimated life of more than three years. The PHAMP-1 has an operational output of +/- 2000 mV. The BNC connector from your coax electrode cable is attached to the BNC receptacle input connection on the PHAMP-1.  The output is a BNC connector. You must have a BNR receptacle on your cable to connect from the output to your controller. Sensorex provides accessory cables and adapters to make this transition. The PHAMP-1 is not water proof; you must protect it from water and the elements.

OEM line powered preamplifiers are more economical over long term and provide the optimum service life for the majority of installations. Refer to the Preamplifier Guide (below) to select the preamplifier. Locate the Original Equipment meter in Column A and order the preamplifier listed in Column B. Download pre-amp wiring diagrams.

For users of simple conventional pH electrodes, our ground loop eliminator box, also known as GLE boxes, can stop measurement problems associated with electrical ground loops.