2 - Installation
Power Bus Connections
CAUTION: Observe polarity when making the power bus connections to both the Agilent MCCD mainframe and the Agilent Powerbus Load. Reversed polarity connections will result in damage to both the Agilent MCCD mainframe and the Agilent Powerbus load. The negative (−) bus bar on the Agilent MCCD mainframe is connected to chassis ground.
Connections to the power bus are made via + and − bus bars on the back of the Agilent E4370A MCCD mainframe and Agilent E4371A Powerbus Load units. These bus bars let you interconnect multiple mainframes, external power sources, and other loads. Bus bars have mounting holes that accept 7 mm diameter bolts.
NOTE: Fasten a suitable terminal lug to each power bus cable. Do not connect bare wires directly to the bus bars. Stranded cables with more and smaller diameter wires are easier to work with than cables with fewer and large diameter wires.
When making your power connections you can use discrete terminated wires, bus bars, or combinations of both. For proper operation all power bus configurations should have minimum loop area for low magnetic radiation and should be kept away from CRTs. The following guidelines may be helpful in deciding whether to use wires or bus bars.
Discrete terminated wires:
♦Are the better solution for connecting to individual units and the total current carrying requirements are 120 A or less.
♦Have minimal alignment, insulation or routing problems.
♦Are preferred for small cell charging systems.
Bus bars:
♦Are the better solution for high current carrying requirements.
♦Can be custom designed or purchased; can use standard high current building parts.
♦Use nuts and bolts or self tapped holes for connections.
♦Require careful surface preparation and cleaning at connection points.
WARNING ENERGY HAZARD. If high current power bus connections touch, severe arcing may occur - resulting in burns, ignition, or welding of parts. Do not attempt to make any connections to the power bus when the power bus is live.
Power Bus Wiring Information
The following table provides information about the resistance and ampacity of several standard wire sizes that may be suitable for power bus connections. This information is important because the resistance of the power bus wiring will cause a voltage drop in the power bus wires. If the voltage drop is large enough, it may prevent the Agilent E4370A MCCD mainframe from operating correctly in charging mode, or the Agilent E4371A Powerbus Load from operating correctly in discharging mode.
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