Saber 115V chargers used with 240V

Motoman · Post by **Motoman** » Fri Mar 19, 2004 12:28 am

Can a saber 115V charger be used with 240V if the fuse is changed or is the charger internally built for 115V or is there anyway to swtich it to 240V? Thanks

Will · Post by **Will** » Fri Mar 19, 2004 12:38 am

Motoman, you would probbaly blow the transformer accross the outback.
You could look at he transformer to see if it has two primary windings. They connect the windings in paralell for 117 volts and in series for 240 operation. Most of the time the transformer is different for the 240 volt.

Motoman · Post by **Motoman** » Fri Mar 19, 2004 1:48 am

Ok instead of taking the risk i've taken the charger apart and bypassed the transformer as i'm going to hook up 9V to the charger where the transforms leads connect to the PCB. Question does neg itive and postive matter if so which one is + and - ?

N4UMJ · Post by **N4UMJ** » Fri Mar 19, 2004 10:58 am

MOTOMAN....

I received a NTN4786A 220VAC charger and it had provisions by reconfiguring (rotating) the fuse holder to set it up for 115VAC operation. There are about three or four wires there that go to the primary of the transformer and also the fuse holder. The fuse holder does double duty as a Primary Voltage selection switch. Mine is working fine here.

I know you did not ask about 220 to 110 conversion but this also leads me to believe on the NTN4734A that it can be reconfigured in the reverse as well as it has the same voltage selector fuse holder. The fuse would need to be changed to a higher voltage type which in mine is a 400mA @ 250VAC.

Maybe someone else has the specific MOTO documentation on doing this?

Eddie N4UMJ

Motoman · Post by **Motoman** » Fri Mar 19, 2004 12:02 pm

thanks guys you've been a great help yeah my smart charger can do that i just have to change the fuse holder around. Although it's a little late i blew the fuse but i just have to get a new one.

N4UMJ · Post by **N4UMJ** » Fri Mar 19, 2004 12:27 pm

Forgot to mention in case you did not know the NTN4786A and the NTN4734A are both Saber Desktop Rapid Chargers and only differ in what I can tell by the fuse position and label.

Here again I don't have a schematic or other documentation supporting it's use on both 220 and 115 but it seems Motorola allowed it to be configured to do both.

In addition my 220 VAC NTN4786A charger label calls for a "5 X 20 .4A 250V SLOW BLOW FUSE". Again the glass fuse has a stamping of "400mA/250V "(also has a circle with a capital "T" inside of it) on its endcap.

Looking at several other NTN4734A's I have here I see the NTN4734A and NTN4786A both use the same size/rating fuse.

Hope this gets you going in the right direction and best of luck!

Eddie N4UMJ