# iNELS Bus communication

The iNELS bus utilizes a twisted pair cable for both power and data transfer, operating at DC 27V. The rated voltage of the bus system is 27 V, and the voltage provided by the power supplies is 27 V. The bus devices work without error at voltages between 21 V and 27 V, so a tolerance range of 6 V is available to compensate for voltage drops in the cable, and contact resistance. In the bus system, bus separator units, BPS3-01M and BPS3-02M units are used for impedance separation of the BUS from the supply voltage source. The outputs are equipped with overcurrent and surge protection.

The iNELS bus utilizes a twisted pair cable for both power and data transfer, operating at a DC voltage of 27V. The rated voltage of the bus system is 27V which matches the voltage provided by the power supplies.

{% hint style="info" %}
The bus devices in the iNELS bus system are designed to operate without errors within a voltage range of 21V to 27V. This provides a tolerance range of 6V to compensate for voltage drops in the cable and contact resistance, ensuring reliable operation of the devices.
{% endhint %}

<figure><img src="/files/uzzWEU8qXQD48p60XSuM" alt="" width="375"><figcaption><p>Wiring diagram with bus separator</p></figcaption></figure>

**To achieve impedance separation between the bus and the supply voltage source, the iNELS bus system employs bus separator units, specifically the BPS3-01M and BPS3-02M units. These units are responsible for isolating the bus from the power supply voltage source, ensuring proper data transmission and protection. Additionally, the outputs of the bus separator units are equipped with overcurrent and surge protection. This helps safeguard the connected devices and the bus system itself from potential damage caused by excessive current or voltage surges.**


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