3.2. Cabinet Installation
The ML Series MagnaDC power supply ships as a self-contained floor-standing cabinet and requires no rack or external enclosure. 500 kW models combine the power supply and harmonic neutralizer in a single, connected three-cabinet assembly. 1000 kW models are supplied as two cabinets — a power supply and a harmonic neutralizer — which are placed side by side and joined at installation as described in Harmonic Neutralizer Interconnection. Refer to Product Diagrams for cabinet dimensions and to the Physical Specifications for weights.
The unit must be operated in the upright position.
3.2.1. Moving and Positioning
Each cabinet is built on a heavy-duty welded pedestal base and must be moved with a forklift or pallet jack. The bottom panel of both the power supply cabinet and the harmonic neutralizer cabinet is designed to carry the full weight of the unit.
When lifting with a forklift, position the forks just outside the two centre welded pedestal members, with the front of the cabinet facing the forklift. Move the cabinet only on a level surface, and follow the uncrating instructions sheet included with the shipment when removing it from its pallet.
Warning
ML Series cabinets weigh between 5000 lbs (2268 kg) and 6800 lbs (3084 kg). Confirm that the lifting equipment, the route to the installation site, and the floor at the installation site are rated for the weight before moving the cabinet.
Once the cabinet is in its final position, secure it to the floor through the mounting holes provided in the pedestal base.
3.2.2. Clearances and Service Access
All user connections — AC input, DC output, coolant, remote sense, and the external user I/O and communication interfaces — are made at the rear of the cabinet. Magna-Power recommends a minimum of 3 feet (0.9 m) of clear space behind the cabinet, both to make these connections and for subsequent service access.
All internal assemblies are designed to slide out from the front or the rear of the cabinet, so side access is not required once the cabinet is in position. On 1000 kW systems, access between the power supply and harmonic neutralizer cabinets is required while they are being interconnected, and access to the right-hand side of the harmonic neutralizer is required if the two cabinets ever need to be separated again.
Power and control cables must be kept separate: run them in independent conduits and feed them through dedicated holes punched in the rear access panel. Routing control wiring alongside the AC input or DC output conductors can couple switching noise into the analog programming and monitoring signals.
3.2.3. Cooling Requirements
The ML Series is water cooled. The majority of the heat it produces leaves through the coolant, and the installation must supply coolant meeting the requirements in Water Cooling and in the Environmental Specifications. The ML Series is rated for continuous full-power operation in ambient temperatures up to 50 °C.
The remainder of the heat is rejected to the air by internal fans, which draw fresh air in at the bottom of the cabinet and exhaust warm air through the top. No external fans are required.
Caution
Blocking ventilation will cause the power supply to overheat and trip the thermal (THL) diagnostic. Do not obstruct the air intakes at the base of the cabinet, and leave the top exhaust clear. Do not place the cabinet beneath a low overhang or shelf that would restrict the top exhaust.
The room or enclosure housing the ML Series must be able to remove both the heat carried away by the coolant and the heat rejected to the air. The following table gives the maximum of each at full load, calculated from the maximum rated output power and the lowest published efficiency for that power level, with losses distributed approximately 80% to the coolant and 20% to ambient air.
Note
The values above are the worst case across the models at each power level. A specific model rejects less heat in proportion to its published efficiency: a 96% efficient 1000 kW model, for example, rejects approximately 33 kW to the coolant rather than the 69.6 kW shown. Size the chiller from the efficiency of the model actually ordered, and for master-slave systems multiply by the number of cabinets.