4.4ELECTRICAL INSTALLATION

Hydrastep 2468CB & 2468CD Manual

Remote Display Options 24683B, C & D

4.4ELECTRICAL INSTALLATION

Up to six remote displays may be driven by the Hydrastep 2468 unit. One remote display can be powered from the main unit, but all the others must have a local supply. A remote display has a dual serial data input and a dual power input. When the remote display is powered from the main unit an eight-core cable is required to connect the two units. When a remote display is locally powered, however, a six-core cable will suffice. See the example in Figure 4.4: remote display unit 1 is powered from the main unit and uses an eight-core cable; remote display unit 2 is locally powered and uses a six-core cable. All cables must be screened to

comply with the EMC directive.

For remote displays powered from the main unit the loop resistance of the power conductors must be less than 27 ohms for an a.c. powered unit or 7 ohms for a d.c. unit. To provide for cable runs of up to 1000 metres, without the use of heavy cables, the main unit and the remote display unit each have internally linked multiple terminals for the power and ground connections. This allows the power and ground lines to be doubled to reduce the loop resistance.

Figure 4.2 - Interconnection cable for a single remote display

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Emerson 2468CD, 2468CB manual 4.4ELECTRICAL INSTALLATION, comply with the EMC directive