Frequently Asked Questions


What is a digital interface?

ISAscale® products primarily have digital output signals. These include CAN, SPI, LVDS, TTL, RS422, RS485, RS232 or Ethernet. Details can be found on the product-specific data sheet.

What is an analog interface?

Standard analog signals have the range of 4-20 mA and 0-5 (10) V. There are ratiometric analog signals whose reference value is determined by the customer. Isabellenhuette Heusler GmbH & Co. KG has set itself the task of offering purely digital solutions.  Isabellenhuette Heusler GmbH & Co. KG is thus pursuing the market trend.

Voltage measurement

Why are there 2 pins for the IVT voltage measurement?

The IVT series has a connector with 2 pins for the voltage measurement. However, it is to be ensured that both pins are connected to each other (short-circuited) and serve as the high-voltage potential tap. The referencing mass is the shunt ground. Data sheet IVT-S

What is the installation orientation?

It generally does not matter how the IVT-S is installed, since the signs for the current direction can be adjusted. However, it is to be noted that an offset of several mV can be given during the voltage measurement, since there is a certain voltage drop across the shunt. It is therefore recommended to install the sensor as stated in the data sheet to ensure a precise

Current measurement

How is current measured?

The basic principle of current measurement with the help of a shunt is based on the Ohm's law, the well-known formula U=R*I. If current flows through a resistor (shunt), voltage drops across the resistance element. This voltage is in a linear relationship with the change of the current flowing through the resistor. Using special measurement methods, we can very precisely determine, digitize and evaluate this voltage.

How is such high accuracy achieved by shunt-based measurement?

The accuracy is based on multiple factors: In the beginning, Isabellenhütte in cooperation with a supplier of semiconductors, developed low-noise and low-offset semiconductor components which are used throughout our products. Nowadays the shunts produced by Isabellenhütte use resistive materials for their sensitive element, which are melted and processed in-house. This provides a full control of physical and mechanical properties of the materials which results in compliance of the products with the requirements due to specific field of use.

With the help of the company-owned certified calibration laboratory (DAkkS), Isabellenhütte achieves highly accurate current and voltage measurement throughout the production process and with it the transfer of this accuracy to the products. Therefore, all products are also in line with national standards.

What current ranges are covered by ISAscale® products?

Depending on the product family, ISAscale® products cover current ranges from 0 A to 30 kA in both positive and negative direction of current.

How are shunt connectors designed?

The shunts standard shape is flat and comes with a M8 drilling. On request, Isabellenhütte can provide specific shunt shapes, like U or L shapes. Shunts can even be manufactured in a three-dimensional way. Depending on your application and space we can provide you a tailor-made shunt.  The shunt can be part of the current bus bar, which allows a space-saving construction.


Initial accuracy

The initial accuracy is the value, which is achieved at the end of the production process.

Total accuracy

As the sensor consists of many components whose properties change over time, as a matter of course the performance of the sensor also changes. Hence, we additionally provide the total accuracy indicator for the worst case, which can occur over life time of the product.

Accuracy of the indicated value (relative error)

The accuracy is always displayed as accuracy of reading, never of range. E.g. if 10 A are measured with an accuracy of 0.1%, the error is 0.01 A, at 100 A the error is 0.1 A. Only the offset is displayed as an absolute error (of range).

Temperature calibration

Advantages of a temperature calibration

The temperature compensation, which is done within the calibration process, provides high accuracies in current and voltage measurement, independent from the temperature.

Commercial questions

How/where can I buy an ISAscale® product?

To buy our products, just get in touch with your local sales agent by following the link. Contact

Can I get a product sample?

In case you need a sample for testing, just ask your local sales agent for a quote. Contact

Does Isabellenhütte support colleges and universities?

Research and Innovation have always been of big interest for Isabellenhütte. Therefore, we’re very pleased to support your university project. Please contact us to elaborate how we can help you with your research.

Can I get a product for rent?

At the moment Isabellenhütte doesn’t offer products for rent.

Methods of Payment

When do I have to pay my invoice?

Our standard payment conditions require a payment within 30 days after receiving the invoice. Cash discount cannot be given.
Can I pay with credit card? At the moment, payment with credit card is not possible.

Is it possible to pay by credit card?

Unfortunately we are not able to accept credit card.


Is there a customer service available?

For technical or commercial questions we are pleased to help you via phone +49 2771 934-258 or email