MFJ -4275MV User manual

MFJ-4275MVnstruction Manual

Thank you for purchasing the MFJ-4275MV Switching Power Supply.
The MFJ-4275MV is designed to deliver output current up to 75 Amps
intermittent or 70 Amps continuous at 13.8 Vdc.

Five types of output terminals are provided – 2 sets Anderson Powerpole®, 2
sets of 5-way binding posts, 2 sets of quick connect terminals and a cigarette
lighter socket. The variable output control adjusts output from 4 Vdc to 16 Vdc.
Output control has a pre-set detent position, which sets the output at 13.8Vdc.
The battery charger provides charging current up to 20 Amps peak and 5 Amps
continuous.

The total combined output current for this power supply is 75 Amps intermittent
or 70 Amps continuous at 13.8 Vdc. Each output connection has its output
current limit as shown by the following chart. Do not draw current over the
rated limited.

Output Connections Maximum combined output current is 75

Amps, Intermittent
Gold 5-way binding posts 75 Amps
Black and Red binding Posts 40 Amps
Anderson Power Poles 35 Amps
Quick Connect Terminals 10 Amps
Cigarette Lighter Socket 10 Amps

Installation

Before plugging the MFJ-4275MV in an AC outlet make sure that the proper
input AC voltage is set to the correct AC voltage you are using. Select 115 for
100/110/120 AC operation or select 230 for 200/220/240 ac operation. 115V is
the default factory setting. Do not connect any device to the power supply yet.
Turn the power supply ON. Set the output voltage by adjusting the variable
output control in front of the power supply. The MFJ-4275MV has variable
output adjustment from 4 Vdc to 16 Vdc. The control will set the same output
voltage for all output connectors. The detent position on the output control sets
the output voltage at 13.8Vdc. Turn OFF the power supply after setting the
output voltage.

Connect the loads to the any of the output connectors. Positive to positive
terminal and negative to negative terminal. Reversed connection will damage
your equipment. For Anderson Powerpoles® connection, please refer to “the
assembly instruction” for detail assembly instructions. Connect the devices to
the power supply then turn ON the power supply.

Protection

The MFJ-4275MV has fault protection for output terminal short or overload
(over 75 Amps), over voltage (pre-set at 16 Vdc) and component over heated. If
any the above conditions occur, the warning LED will come on. Under fault
condition, the power supply will automatically shut off. To reset, turn the unit
OFF and wait 20 seconds, then turn the unit back on.

Battery Charger

MFJ-4275MV has built-in battery charging circuit. Battery to be charged must
be connected to the charger output binding posts on the back of the unit.
Charging output is set at 13.8 Vdc fix. Maximum charging current is 20 Amps
for 20 seconds and 5 Amps continuous. When the battery reaches its capacity
the charging circuit will reduce charging current to trickle charge at 30 mA.

Powerpole® connector assembly

Two sets of Anderson Powerpoles® connectors are provided.
The terminals accommodate wires from 12 to 16 gauge.

Follow the following instructions to assemble the connectors.

First, slide two connector housings together to match the configuration
of the corresponding connectors on your power strip. It’s easier to do
this now rather than after the wired terminals have been inserted in the
housings.
You can install the Powerpoles® connectors on your wires by either
soldering or crimping, as long as you make sure you have good, solid
connections. Wires smaller than 12 gauge will not allow for crimping,
and must be soldered to the terminals.

To crimp, first strip the wire, making sure not to damage the wire strands.
Insert the wire into the terminal and crimp. Be careful not to deform or
squash the terminal body. If you do, crimp again to return it to its original
shape. Otherwise, the terminal may not fit inside the housing. Be sure that
you have a good firm connection to reduce resistance.

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If you solder wires to the terminals, tin them lightly first. When
soldering, flow solder only into the hole in which the wire is inserted.
Be careful not to get any solder around the outer body of the terminal.

F ig 3: Correct orientation of
terminal and housing.

Fig 4: Using an insertion tool to
snap terminal in place. A very
small, flat-blade screwdriver will
work.

Fig 5: Assembled terminal and
housing.

Then insert the flanged end of
the terminal into the contact
housing through the open,
square end of the housing
(Figs. 3, 4 and 5). The terminal
will snap into place when
correctly oriented.

Internal view of two Powerpoles® connected.

(Anderson Power drawings;

www.andersonpower.com)

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MFJ LIMITED 12-MONTH WARRANTY

MFJ Enterprises, Inc. Warrants to the original owner of this product, if manufactured by
MFJ Enterprises, Inc. and purchased from an authorized dealer or directly from MFJ
Enterprises, Inc. to be free from defects in material and workmanship for a period of 12
months from date of purchase provided the following terms of this warranty are satisfied.

1. The purchaser must retain the dated proof-of-purchase (bill of sale, canceled check, credit card or
money order receipt, etc.) describing the product to establish the validity of the warranty claim
and submit the original of machine reproduction or such proof-of-purchase to MFJ Enterprises,
Inc. at the time of warranty service. MFJ Enterprises, Inc. shall have the discretion to deny
warranty without dated proof-of-purchase. Any evidence of alteration, erasure, or forgery
shall be cause to void any and all warranty terms immediately.

2. MFJ Enterprises, Inc. agrees to repair or replace at MFJ’s option without charge to the original
owner any defective product under warranty, provided the product is returned postage prepaid to
MFJ Enterprises, Inc. with a personal check, cashiers check, or money order for $7.00 covering
postage and handling.

3. This warranty is NOT void for owners who attempt to repair defective units. Technical
consultation is available by calling [phone].

4. This warranty does not apply to kits sold by or manufactured by MFJ Enterprises, Inc.

5. Wired and tested PC board products are covered by this warranty provided on the wired and
tested PC board product is returned. Wired and tested PC boards installed in the owner’s cabinet
or connected to switches, jacks, or cables, etc. sent to MFJ Enterprises, Inc. will be returned at the
owner’s expense un-repaired.

6. Under no circumstances is MFJ Enterprises, Inc. liable for consequential damages to person
property by the use of any MFJ products.

7. Out-of-warranty Service: MFJ Enterprises, Inc. will repair any out-of-warranty product provided
the unit is shipped prepaid. All repaired units will be shipped COD to the owner. Repair charges
will be added to the COD fee unless other arrangements are made.

8. This warranty is given in lieu of any other warranty expressed or implied.

9. MFJ Enterprises, Inc. reserves the right to make changes or improvements in design or
manufacture without incurring any obligation to install such changes upon any of the products
previously manufactured.

10. All MFJ products to be serviced in-warranty or out-of-warranty should be addressed to MFJ
Enterprises, Inc., 300 Industrial Park Road, Starkville, Mississippi 39759, USA and must be
accompanied by a letter describing the problem in detail along with a copy of your dated proof­of-purchase.

11. This warranty gives you specific rights, and you may also have other rights which vary from state
to state.

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