3. Installation¶
3.1. Inspection¶
Carefully unpack the SL Series MagnaDC power supply and accessories saving all packing materials and included enclosures. Inspect 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: magna-power.com/support.
The following parts are included with all MagnaDC power supply models:
SL Series MagnaDC power supply
RS232 Cable (Male to Female)
AC input metal terminal cover
DC output metal terminal cover
Qty (2) rear support brackets for rack installation
Qty (16) 10-32 screws
Qty (8) 10-32 flat washers and lock washers
Qty (2) handles with mating hardware
USB drive with software, drivers, and digital documentation
NIST traceable calibration certificate
3.2. Rack Installation¶
The SL Series MagnaDC power supply is intended for rack mount installations only and is designed to fit in standard 19-inch EIA equipment racks. The SL Series product is designed to fit in one rack-unit (1U). Additional support, other than that provided by the front panel, is required. Fixed rear support rails are provided, which can be adjusted at time of installation to fit a variety of equipment rack depths. These included rails are designed to mate to inserts on the SL Series side panels using included hardware. Alternatively, angle slides or cross beam supports can be used to securely fasten the product to the rack and support the rear weight. The unit should be horizontally mounted.
Fig. 3.1 Included rear support rails for SL Series (inches). Click for a larger view.¶
3.2.1. Cooling Requirements¶
Each SL Series MagnaDC power supply is cooled by suitable fans exhausting warm air to the rear of the cabinet. Fresh air intake is from the sides of the cabinet allowing two or more SL Series supplies to be stacked without any clearance required. Equipment racks should be equipped with fans or blowers to remove heat generated by the power supplies. Magna-Power recommends fresh air intake at the bottom of the cabinet and exhaust fans at the top pulling air out of the cabinet.
The SL Series MagnaDC power supply features integrated fans that pull in cool air from sides and exhausts warm air from the rear. Air intake from only the sides of the product allow two or more SL Series MagnaDC power supply to be stacked with zero clearance between units. Equipment racks housing the SL Series MagnaDC power supply should be equipped with either an open back, back with grills, or closed back with cabinet fans to remove heat generated by the SL Series MagnaDC power supply. For fully enclosed cabinets, Magna-Power recommends fresh air intake from the bottom of the cabinet and exhaust at the top.
For cabinet fans to be effective, the ambient intake air temperature outside the rack must be less than the air temperature inside the rack. The SL Series MagnaDC power supply is rated for 50 °C ambient operating temperature. In the case of rack installation, this corresponds to the temperature inside the rack and adequate cooling measures must be taken to ensure the rack’s internal temperature stays below 50 °C.
The following table provides Magna-Power’s recommended per unit cabinet air flow when installing the SL Series MagnaDC power supply in a fully enclosed cabinet:
SL Series Model Power Level |
Maximum Heat Produced |
Recommended Cabinet Air Flow
77 °F (25 °C) Room Temperature
|
Recommended Cabinet Air Flow
104 °F (40 °C) Room Temperature
|
|---|---|---|---|
1.5 kW |
0.5 kBTU/hr |
15 CFM |
35 CFM |
2.6 kW |
0.9 kBTU/hr |
25 CFM |
65 CFM |
4 kW |
1.4 kBTU/hr |
25 CFM |
80 CFM |
6 kW |
2.1 kBTU/hr |
50 CFM |
120 CFM |
8 kW |
2.7 kBTU/hr |
65 CFM |
160 CFM |
10 kW |
3.4 kBTU/hr |
80 CFM |
200 CFM |
Note
The table above accounts for only a single power supply at each respective power level. When sizing cabinet fans, it is necessary to account for the heat produced by all the products in the cabinet.
Caution
Do not block the air intake on the front or sides of the instrument, nor the exhaust at the rear of the instrument. Blocking these vents could cause the product to overheat. The recommended minimum clearances are 2 inches (5.1 cm) along the sides and back.
3.3. AC Input Connection¶
Warning
Disconnect AC power from the mains and measure the AC input terminals to ground to ensure 0 Vac is present before attempting any installation procedure.
AC power is wired to the SL Series MagnaDC power supply by attaching three cables plus ground for 3-phase installations or two cables plus ground for 1-phase installations. The SL Series MagnaDC power supply is phase orientation insensitive, allowing the phases to be connected in any order; the ground connection, however, must be connected to ground stud labeled with a ground symbol.
Magna-Power recommends cables per the recommendations of the National Electrical Code or Suggested Ampacities of 4-Conductor Type S or SO Cable, with one end stripped of 0.5 in (12.7 mm) of insulation and securely fastened to the 38660 Molex input connector at the rear of the power supply. For additional connection security, crimp the end of AC wire with a fork terminal with an outer end-to-end fork width of no more than 0.4 in (10.2 mm).
Note
The cable recommendations provided are for reference purposes only. Always consult local electrical code requirements to ensure compliance.
After connections are made, the provided protective covers for the AC input and DC output can optionally be installed and securely fastened to the chassis using three screws per cover. This programmable DC power supply is designed to be permanently connected to the power source requiring a readily accessible disconnect device incorporated into the fixed wiring.
Wire Size |
60 °C Types |
75 °C Types |
85 °C Types |
90 °C Types |
|---|---|---|---|---|
RUW, T, TW |
FEPW, RH, RH, RUH, THW, THWN, XHHW, ZW |
V, MI |
TA, TBS, SA, AVB, SIS, FEP, FEPB, RHH, THHN, XHHW |
|
14 AWG |
25 Aac |
30 Aac |
30 Aac |
35 Aac |
12 AWG |
30 Aac |
35 Aac |
40 Aac |
40 Aac |
10 AWG |
40 Aac |
50 Aac |
55 Aac |
55 Aac |
8 AWG |
60 Aac |
70 Aac |
75 Aac |
80 Aac |
6 AWG |
80 Aac |
95 Aac |
100 Aac |
105 Aac |
4 AWG |
105 Aac |
125 Aac |
135 Aac |
140 Aac |
3 AWG |
120 Aac |
145 Aac |
160 Aac |
165 Aac |
2 AWG |
140 Aac |
170 Aac |
185 Aac |
190 Aac |
1 AWG |
165 Aac |
195 Aac |
215 Aac |
220 Aac |
10 AWG |
195 Aac |
230 Aac |
250 Aac |
260 Aac |
20 AWG |
225 Aac |
265 Aac |
290 Aac |
300 Aac |
30 AWG |
260 Aac |
310 Aac |
335 Aac |
350 Aac |
40 AWG |
300 Aac |
360 Aac |
390 Aac |
405 Aac |
250 MCM |
340 Aac |
405 Aac |
440 Aac |
455 Aac |
300 MCM |
375 Aac |
445 Aac |
485 Aac |
505 Aac |
350 MCM |
420 Aac |
505 Aac |
550 Aac |
570 Aac |
Wire Size |
Maximum Current |
|---|---|
18 AWG |
7 Aac |
16 AWG |
10 Aac |
14 AWG |
15 Aac |
12 AWG |
20 Aac |
10 AWG |
25 Aac |
8 AWG |
35 Aac |
6 AWG |
45 Aac |
4 AWG |
60 Aac |
2 AWG |
80 Aac |
3.3.1. Fuse Rating¶
MagnaDC power supplies contain a variety of power and control fuses. For MagnaDC power supply products with a 1-phase input, there are two (2) power fuses and two (2) control fuses. For MagnaDC power supply products with a 3-phase input, there are three (3) power fuses per module and two (2) control fuses per module. The SL Series fuse table provides the fuses ratings and recommended replacements. Magna-Power recommends using a time-delay fuse.
In the event of a fuse fault, power must be removed from the supply and the fuse must be replaced to correct this condition. A cleared power fuse usually indicates a power stage failure, often requiring factory attention. In addition, a cleared fuse can be caused by power surges from lightning storms or other AC transient events.
Warning
To avoid personal injury or damage to the SL Series MagnaDC power supply, use only the specified replacement fuses.
Power Level |
AC Input Voltage |
Power Fuse Rating |
Recommended
Power Fuse(s)
|
Control Fuse Rating |
Recommended
Control Fuse
|
|---|---|---|---|---|---|
1.5 kW |
85-265 Vac (UI) 1-Phase |
Qty (2) at 25 Aac ea. |
FNQ25 |
Qty (2) at 1 Aac ea. |
FNQ1 |
1.5 kW |
208/240 Vac 3-Phase |
Qty (3) at 8 Aac ea. |
FNQ8 |
Qty (2) at 1 Aac ea. |
FNQ1 |
1.5 kW |
380/415 Vac 3-Phase |
Qty (3) at 5 Aac ea. |
FNQ5 |
Qty (2) at 1 Aac ea. |
FNQ1 |
1.5 kW |
440/480 Vac 3-Phase |
Qty (3) at 5 Aac ea. |
FNQ5 |
Qty (2) at 1 Aac ea. |
FNQ1 |
2.6 kW |
187-265 Vac 1-Phase |
Qty (2) at 25 Aac ea. |
FNQ25 |
Qty (2) at 1 Aac ea. |
FNQ1 |
2.6 kW |
208/240 Vac 3-Phase |
Qty (3) at 15 Aac ea. |
FNQ15 |
Qty (2) at 1 Aac ea. |
FNQ1 |
2.6 kW |
380/415 Vac 3-Phase |
Qty (3) at 8 Aac ea. |
FNQ8 |
Qty (2) at 1 Aac ea. |
FNQ1 |
2.6 kW |
440/480 Vac 3-Phase |
Qty (3) at 8 Aac ea. |
FNQ8 |
Qty (2) at 1 Aac ea. |
FNQ1 |
4 kW |
208/240 Vac 3-Phase |
Qty (3) at 20 Aac ea. |
FNQ20 |
Qty (2) at 1 Aac ea. |
FNQ1 |
4 kW |
380/415 Vac 3-Phase |
Qty (3) at 10 Aac ea. |
FNQ10 |
Qty (2) at 1 Aac ea. |
FNQ1 |
4 kW |
440/480 Vac 3-Phase |
Qty (3) at 10 Aac ea. |
FNQ10 |
Qty (2) at 1 Aac ea. |
FNQ1 |
6 kW |
208/240 Vac 3-Phase |
Qty (3) at 25 Aac ea. |
FNQ25 |
Qty (2) at 1 Aac ea. |
FNQ1 |
6 kW |
380/415 Vac 3-Phase |
Qty (3) at 15 Aac ea. |
FNQ15 |
Qty (2) at 1 Aac ea. |
FNQ1 |
6 kW |
440/480 Vac 3-Phase |
Qty (3) at 15 Aac ea. |
FNQ15 |
Qty (2) at 1 Aac ea. |
FNQ1 |
8 kW |
208/240 Vac 3-Phase |
Qty (3) at 35 Aac ea. |
FNQ35 |
Qty (2) at 1 Aac ea. |
FNQ1 |
8 kW |
380/415 Vac 3-Phase |
Qty (3) at 20 Aac ea. |
FNQ20 |
Qty (2) at 1 Aac ea. |
FNQ1 |
8 kW |
440/480 Vac 3-Phase |
Qty (3) at 20 Aac ea. |
FNQ20 |
Qty (2) at 1 Aac ea. |
FNQ1 |
10 kW |
208/240 Vac 3-Phase |
Qty (3) at 40 Aac ea. |
FNQ40 |
Qty (2) at 1 Aac ea. |
FNQ1 |
10 kW |
380/415 Vac 3-Phase |
Qty (3) at 25 Aac ea. |
FNQ25 |
Qty (2) at 1 Aac ea. |
FNQ1 |
10 kW |
440/480 Vac 3-Phase |
Qty (3) at 20 Aac ea. |
FNQ20 |
Qty (2) at 1 Aac ea. |
FNQ1 |
3.4. DC Output Connection¶
Warning
SHOCK HAZARD. Turn off AC power before making any rear panel connections. Ensure that MagnaDC power supply connections, load wiring, and load connections are either insulated or covered so that no accidental contact with lethal output voltages can occur.
The DC output of the SL Series MagnaDC power supply connects to the DC bus by attaching two cables to the output bus bars. Magna-Power recommends DC power 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 15 lb-ft (20.3 Nm).
Select a wire size sufficient to handle the maximum output current of the unit, no matter what the intended load current or current limit setting.
The recommended wire size for different current levels are shown in the table below.
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 holes for additional cable feeds or direct bus bar connection to the load.
Warning
FIRE HAZARD. Select a wire size large enough to carry the SL Series MagnaDC power supply model’s maximum rated current to prevent overheating of the wires. Make sure power cable connections are secured tightly in accordance with the torque recommendation to prevent overheating of the bus bars.
3.4.1. Grounding the DC Output¶
The output of the SL Series MagnaDC power supply is floating up to the DC output isolation specifications. A floating output means the output terminals are not connected electrically to ground and the produced output voltage is from the positive terminal with respect to the negative terminal. Neither output terminal needs to be connected to ground, however if desired, either the positive or negative terminal can be connected to earth ground.
3.5. Protective Cover¶
The SL Series MagnaDC power supply includes a protective cover for the DC input and a second protective cover for the DC output and remote sense terminals. For oritentation and extra mechanical security, a small notch on the SL Series top panel is designed to mate with the lip on cover. Additional, there are three mating screws, detailed further below.
Before attaching the DC output cover, DC output and remote sense connections should first be made to the terminals. Open the cover’s insulative feed-through by locating the larger of the two black fiberglass pieces. Loosen this black fiberglass piece by turning the screw on both sides of this piece one full turn counterclockwise.
With DC output and remote sense connections made, feed the other end (load side) of these cables through the inside of the protective cover. A small insulated circular cutout is located to the left of the black fiberglass piece, intended for the remote sense connection. The power cables should be fed between the larger black fiberglass pieces. Slide the cover back on the SL Series and mate the cover to the notch on the SL Series top panel. Align the screw holes and secure the cover using included mating hardware.
Finally, tighten the black fiberglass insulator on the cables and secure this insulator in place by tightening its screws.
The same process is repeated for the AC input covers.
3.6. Remote Sense Connection¶
Fig. 3.2 Remote sense connector¶
Note
Wired remote sense is only available for models rated ≤ 1000 Vdc and without the High Isolation Output (+ISO) option.
Remote sensing can improve regulation at a remote reference point. Appreciable voltage drop can occur in the wire between the power supply and load as the current increases. By default, the load operates in local sense, where feedback is internally connected at the power supply’s outputs terminals. However, the power supply can also operate in remote sense, and compensate for wire voltage drop by connecting its high-impedance sense wires to the load terminals. When the remote sense setting is enabled the feedback measurements are taken from the remote sense leads.
Fig. 3.3 Local Sensing (a) and Remote Sensing (b) schematic representation¶
The remote sense setting is accessible from either the front panel configuration or by computer command. Magna-Power recommends using 20 AWG wires with the remote sense screw terminals. Connect the MagnaDC power supply’s positive remote sense lead to the positive of the DC source terminals. Connect the MagnaDC power supply’s negative remote sense lead to the negative terminal of the DC source. Both remote sense terminals are 6-32 screw connections. Connect the sense leads as close to the load as possible. Do not bundle the sense wire-pair together with the load leads; keep the load wires and sense wires separate.
Caution
Always ensure that the positive remote sense lead corresponds to the positive DC bus and, likewise, that the the negative remote sense lead corresponds to the negative DC bus. Connecting sense wires with an incorrect polarity can result in equipment damage.
Enabling remote sense activates the remote sense lead detector. The remote sense lead detector checks that the remote sense leads have been connected to the load. With the power supply configured for remote sensing and upon enabling power output, the sense location is initially set to local. The sense location is switched to remote upon reaching 7.5% of full scale output voltage. Once the power supply is sensing the voltage remote, as long as the voltage detected is greater than 4.5% of full scale output voltage, the sense location remains remote; if the output voltage detected is less than 4.5%, then the sense location will automatically revert back to local.
Caution
WARNING. Switching remote sense leads or disconnecting remote sense leads while the output is enabled can cause device failure. Only switch or disconnect remote sense leads while the power supply is in standby or turned off.
The remote sense indicator on the front panel will flash when the remote sense functionality has been enabled, but the power supply is remaining in local sense. The power supply will remain in local sense with the REM SEN light flashing if the output voltage never exceeds 7.5% of full scale output voltage or the remote sense lead detector has determined sense leads are not connected. The remote sense indicator will remain flashing until the remote sense detector has detected the presence of remote sense voltage within the limits described above.
3.7. Electrical Check¶
This section describes the electrical checkout procedure for the SL Series MagnaDC power supply. This brief electrical checkout procedure validates the product’s power circuitry and safety features. This procedure should be followed upon receipt of the product and before it is placed into use.
The electrical check for models with the C Version front panel require use of the Remote Interface Software described in Chapter 4, Remote Interface Software. With the software installed and the power supply connected to the desired communications interface, select the appropriate equivalent front panel in the Configuration Setup Panel. Select the Virtual Control Panel in the View Menu to display the virtual SL Version front panel. Follow the procedure below using the Virtual Control Panel from within the Remote Interface Software.
With the power supply off, disconnect the load, set voltage and current potentiometer controls fully counterclockwise, and set the over voltage trip and over current trip settings to maximum, fully clockwise. Connect the power supply to a suitable source of AC voltage. For this test, only 50% of rated AC current is required. Turn the power switch on and observe the indicator lights going through the startup routine. After initialization, the following indicator lights should be on: STANDBY, INT CTL, EXT CTL, and ROTARY. This is the default configuration from the factory.
Maximum Voltage, Open-Circuit
Press the start switch and advance the current control one turn clockwise. The power and voltage control indicators should light. Increase the voltage set point to maximum and then to minimum. DC voltage should increase smoothly from minimum to maximum to minimum as indicated on the meter. Return the voltage control full counterclockwise. Press the stop switch.
Over Voltage Trip, Open-Circuit
To check over voltage trip, press the menu key. This places the power supply in data entry mode to set over voltage trip. Using the up/down arrow keys, enter an over voltage trip set point at half the rating of the power supply. Once the over voltage trip set point has been entered, press the enter key to save the information.
Press the start switch and slowly increase the voltage set point. Over voltage trip should operate at the over voltage trip set point. The over voltage trip (OVT) indicator should turn on, the power and voltage control indicators should turn off, and the supply should shut down. Press the clear key. Now set the over voltage trip set point to maximum which is 110% the full scale rating of the power supply. Again start the supply and observe that the power supply operates normally. With the main power disconnected, connect a short to the power output terminals on the rear panel. Reconnect the main power, set voltage and current controls full counterclockwise, and turn the power switch on.
Maximum Current, Short-Circuit
With the main power disconnected, connect a short across the output terminals of the power supply. Reconnect the main power, set voltage and current controls full counterclockwise and turn the power switch on.
Press the start switch and advance the voltage control one turn clockwise. Increase the current set point to maximum and then to minimum. The power and current control indicators should light. DC current should increase smoothly from minimum to maximum to minimum as indicated on the meter. Return the current control full counterclockwise. Press the stop switch.
Over Current Trip, Short-Circuit
To check over current trip, press the menu key and then the item key one time. This places the power supply in data entry mode to set over current trip. Using the up/down arrow keys, enter an over current trip set point at half the rating of the power supply. Once the over current trip set point has been entered, press the enter key to save the information.
Press the start switch and slowly increase the current set point. Over current trip should operate at the over current trip set point. The over current trip (OCT) indicator should turn on, the power and current control indicators should turn off, and the supply should shut down. Press the clear key. Now set the over current trip set point to maximum which is 110% the full scale rating of the power supply. Again start the supply and observe that the power supply operates normally.
If any of these events do not occur, the supply is defective and should not be operated. Depending on the circumstances, either warranty service or troubleshooting is required.