3.1. Inspection¶
Carefully unpack the MagnaLOAD electronic load and accessories saving all packing materials and included enclosures. Inspect the product for possible shipping damage. Check that there are no broken knobs or connectors, the external surface is not scratched or dented, the meter faces are not damaged, and all controls move freely. Any external damage may be an indication of internal damage. If there is any damage, notify the shipping carrier and Magna-Power immediately.
The following parts are included with all MagnaLOAD electronic load models:
ALx Series MagnaLOAD DC electronic load
USB cable (Type A to Type B)
Rear metal cover with required fastening hardware
Qty (2) rear support brackets
Qty (16) 10-32 screws
Qty (8) 10-32 flat washers and lock washers
USB drive with software, drivers, and digital documentation
Calibration certificate with Declaration of Conformity
AC input cable
3.2. Rack Installation¶
The 1.25 kW and 2.5 kW ALx Series MagnaLOAD DC electronic load models are intended for rack-mount installation, designed to fit in a standard 19” equipment rack. When installing into a rack, both front and rear support is required. Fixed rear rack-mount support brackets are provided for the the product’s rear. The unit should be horizontally mounted.
Caution
The ALx Series MagnaLOAD DC electronic load is too heavy for one person to safely lift and mount. To avoid injury, always seek assistance from a co-worker before trying to lift and install the product into a rack.
The following steps, which reference Fig. 3.1, should be followed when installing the 1.25 kW and 2.5 kW ALx Series MagnaLOAD DC electronic load models into a rack:
Install 8 clip nuts on the rack frame; 4 for front support and 4 for rear support.
Install the rear rails onto the MagnaLOAD electronic load, but not the mating rear rail ears.
While providing support for the MagnaLOAD electronic load, fasten the front ears to the rack using the provided 10-32 screws.
While continuing to provide support for the MagnaLOAD electronic load, attach the mating rear rail ears onto the rear rails using the provided 10-32 screws. Adjust the position of the rear rail ears to align snuggly with the rear rack rails before tightening.
Fasten the rear ears to the rack using the provided 10-32 screws.
Fig. 3.1 Rack mount installation diagram for the ALx Series¶
3.2.1. Cooling Requirements¶
The 1.25 kW and 2.5 kW ALx Series MagnaLOAD DC electronic load models features integrated fans to pull in cool air from the front and sides and exhausts warm air from the rear. Air intake from only the front and sides of the product allow two or more MagnaLOAD electronic load to be stacked with zero clearance between units. Equipment racks housing the MagnaLOAD electronic load should be equipped with either an open back or cabinet fans to remove heat generated by the MagnaLOAD electronic load. If installing these models into an enclosure, Magna-Power recommends fresh air intake from the bottom of the cabinet and exhaust at the top and/or rear.
The 5 kW to 20 kW ALx Series MagnaLOAD DC electronic load models come in a floor-standing enclosure that features integrated fans to pull in cool air from the front and bottom and exhaust warm air from the top and rear.
The following table provides Magna-Power’s recommended cabinet air-flow when installing the 1.25 kW and 2.5 kW ALx Series MagnaLOAD DC electronic load models in a fully enclosed cabinet:
ALx Model Power Level |
Maximum Heat Produced |
Recommend Cabinet Air Flow |
|---|---|---|
1.25 kW |
4.27 kBTU/hr |
400 CFM |
2.5 kW |
8.53 kBTU/hr |
800 CFM |
Caution
Do not block the air intake on the front or sides of the product, nor the exhaust at the rear of the product. Blocking these vents could cause the product to overheat.
3.3. AC Input Connection¶
A single-phase AC input connection is used to provide a ground reference and power for the MagnaLOAD electronic load fans and control circuits. The AC input power requirements are defined on the MagnaLOAD electronic load product rating label. The AC input requirements are further defined in this section.
To provide AC power to the MagnaLOAD electronic load, connect the provided power cord to the IEC 60320 AC power receptacle. The IEC 60320 connector type depends on the product’s AC input power requirement and configuration. For 1.25 kW and 2.5 kW models, an IEC 60320 C13 receptacle is used, as shown in Fig. 3.2. For 5 kW to 20 kW models, an IEC 60320 C19 receptacle is used, as shown in Fig. 3.3.
Fig. 3.2 ALx Series IEC 60320 C13 AC power receptacle¶
Fig. 3.3 ALx Series IEC 60320 C19 AC power receptacle¶
Note
For ALx Series MagnaLOAD DC electronic load models rated 5 kW to 20 kW, the utility side of the provided AC cable is unterminated. The appropriate connector will need to be installed by the user.
Warning
The power cord provides a chassis ground through the third conductor. Be certain that your power outlet is of the three-conductor type with the correct pin connected to earth ground.
The following tables provide the AC input requirements for various ALx Series MagnaLOAD DC electronic load configurations:
ALx Series Rated
Power Level
|
AC Input Voltage
Range
|
AC Input Current
at 120 Vac
|
AC Input Current
at 208 Vac
|
AC Input Current
at 240 Vac
|
|---|---|---|---|---|
1.25 kW |
100-240 Vac (UI) |
1.7 Aac |
1.0 Aac |
0.9 Aac |
2.5 kW |
100-240 Vac (UI) |
1.7 Aac |
1.0 Aac |
0.9 Aac |
5 kW |
100-240 Vac (UI) |
8.2 Aac |
6.8 Aac |
6.2 Aac |
7.5 kW |
100-240 Vac (UI) |
10.3 Aac |
8.2 Aac |
7.3 Aac |
10 kW |
100-240 Vac (UI) |
12.4 Aac |
9.6 Aac |
8.4 Aac |
12.5 kW |
100-240 Vac (UI) |
14.5 Aac |
11 Aac |
9.5 Aac |
15 kW |
100-240 Vac (UI) |
16.6 Aac |
12.4 Aac |
10.6 Aac |
17.5 kW |
100-240 Vac (UI) |
18.7 Aac |
13.8 Aac |
11.7 Aac |
20 kW |
200-240 Vac (UI2) |
N/A |
15.2 Aac |
12.8 Aac |
3.4. DC Input Connection¶
Caution
Disconnect AC power from the mains before attempting any installation procedure.
The input of the ALx Series MagnaLOAD DC electronic load is connected to the DC bus by attaching two cables to the input bus bars, as shown in Fig. 3.4. Magna-Power recommends cables be crimped to ring terminals and securely fastened to bus bars using the included 3/8” bolts, washers, and lock washers. The bus bars contain 3/8”-16 threaded inserts. The recommended torque for the DC connection is 240 in-lbf (27.1 N-m). The recommended wire size for different input currents are shown in the table below.
5 kW to 20 kW models are comprised of multiple modules interconnected by a larger bus bars. Additional fastening locations are available on these models to accommodate their increased power ratings. Larger gauge or multiple parallel wires may be necessary for each terminal. For multiple parallel connections, Magna-Power recommends the wires be the same length from end-to-end.
Fig. 3.4 DC input connection for the 1.25 kW and 2.5 kW ALx Series models¶
The following table provides the suggested DC ampacities of AWG (American Wire Guage) copper wire. Paralleled DC cables may be required for larger-ampacity MagnaLOAD electronic load. Ampacity ratings ar based on single conductor in 25 °C ambient free air, with a conductor rated for 60 °C.
Tip
For DC cabling, Magna-Power highly recommends flexible General Cable Carol® Brand Carolprene® cable, used by Magna-Power and many of its customers.
Caution
Make sure DC connections are tightened in accorandance with Magna-Power’s provided torque specification to avoid overheating of the bus bars.
Wire Size (USA) |
Equivalent Wire Size
(International)
|
Wires Per Output Terminal |
Maximum Current |
|---|---|---|---|
6 AWG |
10 mm2 |
1 |
85 Adc |
4 AWG |
25 mm2 |
1 |
110 Adc |
3 AWG |
25 mm2 |
1 |
130 Adc |
2 AWG |
35 mm2 |
1 |
150 Adc |
1 AWG |
50 mm2 |
1 |
170 Adc |
1/0 AWG |
50 mm2 |
1 |
200 Adc |
2/0 AWG |
70 mm2 |
1 |
235 Adc |
3/0 AWG |
95 mm2 |
1 |
275 Adc |
4/0 AWG |
120 mm2 |
1 |
315 Adc |
1/0 AWG |
50 mm2 |
2 |
400 Adc |
2/0 AWG |
70 mm2 |
2 |
470 Adc |
3/0 AWG |
95 mm2 |
2 |
550 Adc |
4/0 AWG |
120 mm2 |
2 |
630 Adc |
1/0 AWG |
50 mm2 |
4 |
800 Adc |
2/0 AWG |
70 mm2 |
4 |
940 Adc |
3/0 AWG |
95 mm2 |
4 |
1100 Adc |
4/0 AWG |
120 mm2 |
4 |
1260 Adc |
Notes:
Capacity for AWG wires derived from the National Electric Code. Maximum ambient temperature: 40°C. Maximum wire temperature: 90°C. Continuous duty with wires in free air, not bundled or in conduit.
Capacity of aluminum wire is approximately 84% of the capacity listed for copper wire.
For higher current levels, it’s recommended to use bus bars with additional fastening locations allowing for more wire feeds feeds or direct bus bar connection to the load.
A chassis ground reference is also provided on the rear near the DC bus bars, which is tied to the AC input ground. The recommended torque for the ground stud is 55 in-lbf (6.21 N-m).
For rack-mount models, after connections are made, screw the four standoffs into the back panel and place the protective shield over the connections.
For DC bus connections exceeding 315 Adc, Magna-Power recommends multiple runs of 4/0 cabling in parallel. Custom DC bus work may be required to either extend the MagnaLOAD electronic load’s DC bus bars allowing additional DC wire connections, or to make a direct connection with the DC bus work. With increased cable bundling, the ampacity rating of the DC cables will decrease, as less surface area is in free air to cool the wires.