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[/size][/size] hi, my school recently bought one of the Rostock max kits. the thing is now completely built. but now when we plug in the power supply and flip the switch the Rambo board does not light up, -the PSEL jumper is hooked up so that it is on the lower 2 pins (shown in manual) -power strip(input coming from power supply) is connected to board and does supply 12v on each pin(checked with multimeter ), when i attach the usb cord to it ,and that to the computer ,nothing still happens,but when i change the PSEL jumper to the top 2 pins the board lights up and connects to the computer. of course this won't help it because that would mean it was running from the computers supplied 5v. so far for me that means that the power supply is giving 12v but the board is not taking (i checked power in pins connected directly to board with multimeter=works), the fuse is not blown, no wires are detached or reversed from needed position.

any ideas what could be wrong hear ?please reply very soon , my school is trying to show this thing off when it is done,i have been given the responsibility of making it work.

I am not the electronics guru on this forum but I'll try to bump your post to get some attention. The first thing I would do is take and post good pictures of your set up. Pics may trigger some suggestions. Double check everything. I would isolate all the major parts and check their function. Are you trying to hook up an LCD? Lots of issues there, maybe unhook that for now, if you are.
PSU- do you have a second one to swap out and try? When the board powers up under USB what can you do? Do the thermistors function? Very strange that it powers with USB and not on the PSU? Could be a bad board

Does the power supply work? When you turn it on, do you get 12V on the connector that goes to the RAMBo?

g.

Batteau62 wrote:I am not the electronics guru on this forum but I'll try to bump your post to get some attention. The first thing I would do is take and post good pictures of your set up. Pics may trigger some suggestions. Double check everything. I would isolate all the major parts and check their function. Are you trying to hook up an LCD? Lots of issues there, maybe unhook that for now, if you are.
PSU- do you have a second one to swap out and try? When the board powers up under USB what can you do? Do the thermistors function? Very strange that it powers with USB and not on the PSU? Could be a bad board

hi, thanks for the bump. lcd is hooked up, does not turn on when usb powers board. PSU is only a jumper, it works though. when board powers up under USB I can only do things with the lower power items, all end stops and thermistors work on the printer.

I have no idea how to post pics here.

geneb wrote:Does the power supply work? When you turn it on, do you get 12V on the connector that goes to the RAMBo?

g.

yes the power supply works ,found out by multi meter

If the board operates via USB and you've verified the power supply works, then the power connection to the RAMBo is incorrect or faulty.

g.

geneb wrote:If the board operates via USB and you've verified the power supply works, then the power connection to the RAMBo is incorrect or faulty.

g.

unfortunately we did test that connection directly at the pins and they all read 12v also when the usb powers the board the lcd turns on,aslo when I plug the usb in and power the Rambo with it, I only get one green light from the led next to the usb port. when this gets connected to the computer it reads the thermistors and Endstops on the program and then I get tx and rx to light up, all together I am only getting three lights to work.

david wrote:[/size][/size] hi, my school recently bought one of the Rostock max kits. the thing is now completely built. but now when we plug in the power supply and flip the switch the Rambo board does not light up, -the PSEL jumper is hooked up so that it is on the lower 2 pins (shown in manual) -power strip(input coming from power supply) is connected to board and does supply 12v on each pin(checked with multimeter ), when i attach the usb cord to it ,and that to the computer ,nothing still happens,but when i change the PSEL jumper to the top 2 pins the board lights up and connects to the computer. of course this won't help it because that would mean it was running from the computers supplied 5v. so far for me that means that the power supply is giving 12v but the board is not taking (i checked power in pins connected directly to board with multimeter=works), the fuse is not blown, no wires are detached or reversed from needed position.

any ideas what could be wrong hear ?please reply very soon , my school is trying to show this thing off when it is done,i have been given the responsibility of making it work.

There are 3 fuses on the Rambo, did you check them all? (One big fuse, 2 little ones in small sockets)

There are 3 fuses on the Rambo, did you check them all? (One big fuse, 2 little ones in small sockets)[/quote]
where are the two small ones? are they the two tan little things and if so how do you check them?

david wrote:There are 3 fuses on the Rambo, did you check them all? (One big fuse, 2 little ones in small sockets)

where are the two small ones? are they the two tan little things and if so how do you check them?[/quote]
ok I checked all three fuses(assuming the other two were the tan ones near the power supply in) the large fuse is good, but one of the other little fuses is blown(checked by continuity). do you know where we could get another of these?

david wrote:There are 3 fuses on the Rambo, did you check them all? (One big fuse, 2 little ones in small sockets)

where are the two small ones? are they the two tan little things and if so how do you check them?[/quote]

The yellow boxes are the small fuses, ignore the box at the bottom where there is text, you can use your meter set to measure ohms and make sure the fuses read 0 ohms
when you connect to each side of the fuse. (take the fuse from the socket with no power applied first)
If the fuses are bad, see this link for part numbers and you can use up to 10 amp fuses, the originals are 5 amp
http://forum.seemecnc.com/viewtopic.php?t=1001&p=4209

Given that one of the fuses may be blown, you should also first check all of your connections and wiring and make sure there are no stray wires going between connector terminals after replacing the fuse but before applying power again.

Let us know when you replace the bad fuse and if it fixes the problem you had with the Rambo.

Ok, we are ordering them now