Bosch Appliances 9922 141 70691 en manual Cable lengths

DCN Wireless Installation and User Instructions System Design and Planning

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2.6.4Overload indication

Each DCN socket of the central control unit and extension power supply has a red LED that comes on to show that there is a power overload. An overload occurs when:

•The necessary power for the devices is greater than that is supplied.

•A short-circuit occurs.

When an overload occurs, the sockets are deactivated and the connected devices do not operate. The socket checks every 8 seconds (DCN-WCCU) or 30 seconds (DCN-EPS) for power overloads.

2.7Cable lengths

2.7.1Maximum length

The cable length between the central control unit and the furthest device from the central control unit must not be more than 250 m. The cable length includes the device cable and extension cables.

2.7.2To first regenerative tap-off

The total cable length between the central control unit and the first regenerative tap-off socket must not be more than 100 m. This includes the device cables and extension cables.

2.6.5Extension cables

Extension cables (LBB4116) have a direct effect on the available power. The longer an extension cable, the less power is available to drive the connected devices. You must chose the length of the extension cables carefully (refer to section 2.7.5).

2.7.3Between regenerative tap-offs

The total cable length between two regenerative tap-off sockets must not be more than 100 m. This includes the device cables and extension cables.

2.7.4Open-ended DCN cables

‘Open-ended’ DCN cables are DCN cables of which the socket is not connected to a device in the DCN. ‘Open-ended’ cables can cause an incorrect operation of the system. You can ‘close’ the extension cable with a termination plug (refer to the DCN Next Generation Installation and User Instructions). When the ‘open-ended’ cable is connected to a termination plug, the system operates correctly.

2.7.5Power correction

2.7.5.1Introduction

The necessary power from a DCN socket of the central control unit and the extension power supply is affected by:

•The type and number of connected devices.

•The lengths of the connected extension cables.

The power correction graph (refer to figure 2.3) corrects the power level to compensate for the extension cables.

2.7.5.2Calculation

To find the correction for each DCN socket of the central control unit and the extension power supply with the graph, you must first calculate:

•The total power consumption of the devices that are connected to the socket. Refer to section 2.7.5.3.

•The length of the longest extension cable sequence. Refer to section 2.7.5.4.

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