Answers to Frequently Asked Questions about Keller Products

In this article, we have compiled answers to the most popular questions that arise when working with Keller devices. If your question is not on the list, please contact our specialists.

Which power connection scheme should be used for Keller converters?

The power connection scheme for Keller devices differs from the schemes for most other instrumentation and control devices. If there are no special instructions for the device, the connection conditions are as follows:

For analog converters with a 4-20 mA current output signal:
Power supply plus (+Vcc): Black
Output/Ground: White

For analog converters with voltage output (e.g., 0-5 V, 0-10 V, etc.):
Power supply plus (+Vcc): Black
Ground: White
Output signal: Red

For converters with RS485 digital output:
Power supply plus (+Vcc): Black
Ground: White
RS485A: Blue
RS485B: Yellow

Some converter models are equipped with SDI-12 outputs, connected according to the following scheme:
Power supply plus (+Vcc): Red
SDI-12 signal: White
Ground: Black

Please note that the connection scheme for Keller devices is always present on labels, in specifications, and user manuals, which are always supplied with the device. Also, all schemes are available via this link (English)

Why do new converters show over-range readings upon first connection?

The new power supply circuit technology of Keller sensors performs a power network test for current strength, up to 22.5 mA. If the power network fails the test, the converter will hold the output signal at the maximum possible current strength. If this happens, it is necessary to increase the voltage supplied to the converter or reduce the overall load on the power network. More information on power supply requirements for sensors can be found at this link (English)

If the sensor has a digital data transmission option, what are the default settings?

By default, Keller converters are configured to transmit messages consisting of 8 data bits, 1 start bit, and 1 stop bit without a parity bit. The default data transmission rate is 9600 baud (can be changed to 115,200 baud). The default Modbus address is 1. Address 250 is "transparent" — messages sent to it are accepted by all sensors. If only one converter is connected to the bus, this address can be used to communicate with the device whose valid address is unknown. If more devices are connected to the network, each converter's address must be set using the READ30/CCS30 program or by specifying the desired device addresses when placing an order.

How to connect multiple digital converters through one interface?

The general connection scheme can be seen at this link (English)

How to use a third-party RS485 converter with the READ30 software?

Try disabling the "echo" parameter in the communication panel that opens when starting READ30. This setting helps eliminate most connection problems with third-party converters. If data transmission issues persist, you should contact the converter manufacturer. If you want to avoid such difficulties, we recommend using converters produced by us, which guarantee full compatibility with all Keller devices.

How to clear the data logger memory?

There is no manual way to clear the Keller data logger memory because such a function is unnecessary. By default, data loggers will use all available memory. After the memory is filled and all recorded data is downloaded using the Logger DCX software, old data will be overwritten as needed. However, if the "Endless (circular memory)" option is enabled in Logger DCX, the device will cyclically overwrite the oldest data with the newest until the recording process is stopped.

Are there discounts on Keller products for trading intermediaries?

If you wish to become a representative of Izmerkon, please contact us at the email address os@izmerkon.ru