Online prepaid meter and budget systems


The user can check his current balance at any time via the Internet or smartphone and top it up via online payment systems such as Paypal. Alternatively the credit can be topped up by the administration. Furthermore the consumption of the last days and weeks can be checked.

Intelligent dispensing units are installed in the residential units to meet the demand for water, electricity, heat and equipment operating times. According to the set tariff, the consumption is debited from the user's credit balance or also invoiced.

The dispensing units are installed in the residential units and networked by radio or cable. They receive the respective data on the credit balances from the server via a router from the Internet, and the controlled dispensing takes place accordingly.

The convenient software provides a quick overview of all information and transactions. This eliminates the need for time-consuming reading and billing of service charges. This also allows manual topping up of credit by the administration.

The dispensing unit

The dispensing unit can be installed in the sub-distributor of the flats on a HUT rail. The dispensing unit is used for the controlled dispensing of electricity, water, heat and device operating times. For this purpose, either the water meter and valve or the electricity meter and contactor are connected to the dispensing unit. Communication with the router can take place via radio (LoRa) or via cable (RS484). Alternatively, M-Bus or wireless M-Bus meters can be used.

The dispensing unit receives the budgets and credits information, tariffs, configuration, and control data from the server and processes all data locally. This enables accurate billing and dispensing, even if the Internet connection is interrupted or not continuous.

According to the credit/budget and tariff, the valve or contactor opens and closes. The consumption data is regularly transferred to the server, and the credit can be viewed and recharged via smartphone. In case of budget overruns, warnings can be sent via e-mail, SMS, or Messenger. For example, in common rooms, washing machines and dryers can be controlled with the dispensing unit. This makes it possible that the use of the devices is also billed via the student's credit balance. The washing machine is conveniently booked and billed via smartphone.

The credit management

The user can be provided with a monthly or annual budget that is billed as part of the rent or can load and manage his credit balance independently via a web portal on the Internet.

The purchase of credits can be made conveniently by bank transfer or PayPal, for example. The operator of the system sees all transactions in the management software. Furthermore, all customer data, credit sales, number of users, and other statistical data can be created and viewed over any period of time.

Consumption displays in the apartments

To keep an eye on current consumption and the
budget still available, the apartments
can be equipped with terminal displays. Here the
current consumption can be seen at any time and
various statistics can be called up.

  • Display in the apartment with current balance in euros and kilowatt hours/liters, plus consumption trend and forecasts.
  • Notification when the remaining balance falls below a certain value, also possible via SMS and e-mail. 
  • Display of messages and messages from the administration.
    With collection of read receipts.
  • Integration of additional services such as video door intercom possible.

Mobile top-up of credit

The credit is provided as a budget or can be purchased by the user independently via the Internet or by means of a smartphone. The payment is made, thanks to the flexible and conductive interfaces of the system (APIs), through any online payment provider such as PayPal. It is also possible to integrate HBCI and to manually top up the credits by administrative staff.

The request and release of credits is done via secure and encrypted connections to the iSAtech server. The server establishes communication with the dispensing units and all consumption, payment and user information can be conveniently managed through the management software. The paid credit is automatically credited to the user's dispenser. Water, electricity, heating or equipment operating hours can be consumed until the credit is used up or a set credit line is exceeded. A warning informs the user in good time if his credit balance is very low.


  • Prepaid and budgeted dispensing of electricity, heat, water and equipment operating times 
  • Budgeting with annual or monthly budget possible
  • App for the residents: overview of their own consumption, booking of washing machines and dryers as well as independent recharging of credit
  • Warning if budget is exceeded, additional payment if more is needed than budgeted for
  • Online payment (e.g. PayPal, HBCI connection) or convenient credit top-up by the administration.
  • Connection of washing machines, dryers, showers.
  • Connection of displays for the display of consumption data, credit and management messages (message system with read confirmation) possible
  • Usable with iSAtech Prepaid Controller, with M-Bus or wireless M-Bus meters
  • User interface extensively customisable
  • Extensive reporting and evaluation functions
  • No administrative effort: no manual reading, no payment defaults
  • Free and flexible: software as a cloud solution or on-premise
  • Scales perfectly: Profitable already from one installation with one measuring point