The output varies directly as a ratio of the temperatures in K, if the temperature increases the output increases. This is the parameter that automatic temperature compensation in a pH meter compensates for the electrical resistance of the pH glass varies inversely with temperature, as the temperature decreases the resistance increases, roughly doubling every 7 C. Cold measurements increase the resistance of the electrode causing slower, noisier response. The high resistance and low current signal of a pH electrode is extremely susceptible to electrical interference. Inductive and triboelectric noise are the two main types of interference. Inductive noise is generated by moving electrical fields near the cable, an electric motor varying in speed or a person walking by wearing clothing with a high static charge can influence the electrode reading.
Triboelectric noise is a static discharge in the cable caused by moving the cable.
If the cable is shielded from inductive noise and fixed so it doesn't move then cable lengths up to 10 meters can be used. In noisy environments or where cable movement is inevitable the cable should be less than 10 ft. If a longer cable is needed or the environment is noisy, use the battery powered preamp or a built in unity gain amplifier. Flow has little to no effect on the pH reading but can have a major effect on the electrodes overall performance. Particulate matter tends to settle out and bacteria tend to grow on the electrode in non-flowing applications, slowing the response.