Magnum 4K8 Switches Installation and User Guide (10/04)
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The -48VDC terminal block on the Magnum 4K-Series Switch is located on
the right rear of the unit and is equipped
with five (5) screw-down lead posts (see
Fig C5.0). The primary terminals are
identified as positive (A+), negative (A-
), and the secondary power terminals as
negative (B-), positive(B+). The
chassis “earth” or ground (GND), is a
threaded post with a #6 nut.
Figure C5.0: -48VDC Dual-Source, wiring connections to the External
Terminal Block on a Magnum 48VDC with Dual-Source option
Note: The GND should be hooked up first. The 4K unit has a floating ground, so the
user may elect to Ground either + or = terminal to suit the customer’s use.
Before connecting to Terminal block of–48VDC, 24VDC or 125VDC, always
use a digital voltmeter to measure the output voltage of the power supply and
determine the lead which is more “+ve potential”. The more “+ve” voltage lead from
48V or –48V supply must be connected to the post labeled “+”.
The connection procedure is straightforward. Simply connect the DC leads to
the Switch’s power terminals, positive (+) and negative (-) screws. The use of Ground
(GND) is optional; it connects to the chassis. Ensure that each lead is securely tightened.
The 24VDC & 125VDC terminal block on Magnum 4K-Series Switch also has
everything similar to –48VDC info. Described above.
C5.1 UL Requirements
The following must be adhered to in order to conform to UL requirements:
1. Minimum 14 AWG cable for connection to a Centralized DC power source.
2. Fastening torque of the lugs on the terminal block: 9 inch pound max.
3. Centralized DC Power Source cable securement, use at least four cable ties to
secure the cable to the rack at least 4 inches apart with the first one located
within 6 inches of the terminal block.
C6.0 ORDERING INFORMATION
To order the optional Dual-Source -48VDC power supply factory installed,
order “Dual-Src48V” as a separate line item following the product model.
Example: Magnum 4K8-48VDC
Dual-Src-48V for regular model with no ON-OFF switch
Or Dual-Src48V-SWITCH for model with ON-OFF switch
Similarly, order “Dual-Src24V” or “Dual-Src125V” as a separate line item
following the product model.
Example: Magnum 4K8-24VDC or Magnum 4K8-125VDC
Dual-Src24V for regular model with no ON-OFF switch
Dual-Src24V-SWITCH for model with ON-OFF switch
C7.0 OPERATION
Operation of the Dual-Source Magnum 4K-Series-48VDC, 24VDC &
125VDC Switch models are identical to that of the standard models.
36-70VDC
GND
A+ A- B- B+
36-70VDC