STS prepaid metering turns water into a credit balance: the household buys credit, enters a token, and the meter closes its valve when the balance runs out. It is a revenue-protection tool as much as a metering one.
The token
A 20-digit STS token carries an encrypted credit instruction. The household enters it on the meter keypad; the meter validates it, adds the credit and acknowledges on the display. Tokens are generated by the vending system you run, so the credit trail lives on your side as well as on the meter.
The valve
The built-in ball valve is what makes prepaid effective. When credit is exhausted the meter closes; when credit is added it reopens. That also gives you remote shut-off on arrears where the meter has a radio — the reason prepaid and communication are usually specified together.
What it solves
- Arrears. Consumption is paid for before it is delivered, so the debt does not accumulate.
- Reading cost. With a radio fitted, no one needs to enter the unit to read it.
- Disputes. The household can see the balance and the consumption on the meter itself.
What to decide before you specify it
- Prepaid or postpaid. This has to be settled before the specification goes out — a meter installed without a valve cannot be upgraded later.
- Which vending system. The token format and the credit handling sit with the platform you run.
- Whether you need remote shut-off or only local control at the keypad.
- Emergency credit and tariff settings, which are configured per scheme rather than per meter.
Where it fits
Apartment blocks and dormitories with chronic arrears, utility prepaid programmes, and landlord-managed properties where per-unit billing has to be enforced. Valve-equipped prepaid meters are built in household sizes; above that the range moves to other technologies, so confirm the DN early if the project includes larger inlets.