pH, Conductivity & Reference Electrodes FAQs

 

Can we visit?
Please get in touch to arrange a visit to our production facilities in Essex.
Which PH electrodes can I buy online?

We offer a subset of pH electrodes available for delivery within 2-3 working days.
Click here to see the range.

Why should I buy from Sentek?
In a word Quality.
What if I need an electrode that you don't list in your catalogue/website?
Please get in touch – we can make custom electrodes to fit most requirements.
How should I prepare my electrode for use?
Carefully remove the electrode from the packaging and remove the protective rubber or plastic protective “boot” from the tip. Some plastics can leave deposits on the sensing tip which will result in a slow response. Every effort is made to make sure this does not happen, but if you suspect this, then wipe the tip with a tissue soaked in propanol or soak the electrode in cleaning solution (791-15) for an hour.
How do I calibrate my electrode?
Please refer to the Calibration Instructions document.
How do I clean my electrode?
You can clean the tip of the electrode with a tissue soaked in propanol then place in pH buffer to rehydrate. To remove proteins of sample deposits, soak in cleaning solution (791-15) for 1-2 hours.
If working with food or blood products store the electrodes over-night in cleaning solution.
How do I tell if my electrode need replacing?
Set your instrument to absolute mV mode and place the electrode om pH7 buffer. If the reading is greater than ± 30mV, then the electrode may be getting towards the end of its life.
When calibrating between 7 and 4 pH buffers a new electrode should have a slope greater than 95%. If this reading is less than 90%, the electrode may need replacing. (Soaking in cleaning solution may help)
How do I store my electrode?
For short term storage, soak the electrode in storage solution (791-65). If this is not available, HCL at pH4 would be ideal. DO NOT store in DI water or pH buffer. Use tap water is nothing else is available.
How long will my electrode last?
This is application dependant. Using in clean water based samples will result in a lifetime of years.
Food products will result in a shorter life of around 6 months if cleaned properly.
Aggressive chemicals and processes vary quite a lot, but electrodes should have a consistent lifetime.
Does my electrode come with a warranty?
See the linked Product Warranty PDF.
My new electrode will not calibrate.
It is important to make sure the inner stem is free from bubbles. If they are present, shake the electrode in a downwards fashion like a clinical thermometer.
See additional instructions for P19 and P19 knife electrodes.