8mm Forum: Elmo ST800 - Fuse trouble

»	8mm Forum » 8mm Forum » Elmo ST800 - Fuse trouble

UBBFriend: Email this page to someone!

Author

Topic: Elmo ST800 - Fuse trouble

Daniel Florence
Junior
Posts: 13
From: Lyon, France
Registered: Jan 2010

posted February 12, 2011 09:00 AM

Hello, I’m new on this forum ! I’ve been collecting super 8 films for 40 years, mainly cartoons and classic comedies.
I’ve got a question about Elmo ST800 projectors. I have bought two of them, they look as new but the main fuse always burns when I plug the projector. It’s just the same with a 5 A fuse instead of the original 3 A.
Does somebody know where this trouble comes from ? It seems to be quite common with ST800 since I have a third one which can work only with a 5 A fuse.

| IP: Logged

Jean-Christophe Deblock
Jedi Master Film Handler

Posts: 693
From: Grimbergen, Brabant, Belgium.
Registered: Mar 2007

posted February 12, 2011 09:06 AM

Bienvenue Daniel!

I agree.

I have the same problem with mine.

Anybody a solution?

| IP: Logged

Steve Klare
Film Guy

Posts: 7016
From: Long Island, NY, USA
Registered: Jun 2003

posted February 12, 2011 02:30 PM

There's something really wrong here.

I have a 3 amp fuse in my ST-800 and have never blown it in about 8 years of use. Both of you live in places where the line voltage is about double mine, so your line current should be about half, so if I never blow a fuse you should never, never blow a fuse!

The machine that blows the fuse right from the start probably has a short circuit someplace: maybe on the line to the main transformer, maybe inside the transformer itself, maybe something connected on the output side of the transformer.

The key to finding a short is being able to disconnect various circuits in the machine to see which isolated section stays short circuited. The motor section, sound and lamp circuits are controlled by switches, so these can be isolated just by turning them "off". Wherever there is a connector you can isolate just by unplugging it. Sometimes you need to be willing to unsolder a connection and restore it later.

These are times it's handy to be skilled with an Ohmmeter, or make a friend who is.

First things first though: make sure your machine is configured for the local line voltage. I'll give you odds if you plugged mine (set for 115V) into your wall socket, it would blow a fuse too!

--------------------
All I ask is a wide screen and a projector to light her by...

| IP: Logged

Pasquale DAlessio
Film God

Posts: 3523
From: Bristol,RI, USA
Registered: May 2010

posted February 12, 2011 03:14 PM

Steve is correct. However, when working with electrical circuits always go to the source first. If you have a volt meter check the voltage at the outlet first.You want to measure the voltage to see if it's what is reccomended for the unit. Sometimes areas can have increased voltage that will blow the fuse. Then follow Steve's instructions. Good luck finding it.

Pat DAlessio

| IP: Logged

Daniel Florence
Junior
Posts: 13
From: Lyon, France
Registered: Jan 2010

posted February 13, 2011 02:14 AM

Thank you Steve. I have an ohmmeter and I already have checked many things. I'll go on. I hoped maybe anyone knew what's wrong with some ST800...

| IP: Logged

Steve Klare
Film Guy

Posts: 7016
From: Long Island, NY, USA
Registered: Jun 2003

posted February 13, 2011 01:20 PM

The problem you run into here is that you have an AC short, but the ohmeter is a DC device.

If you measure across the primary or secondary of the transformer with an Ohmeter, guaranteed the reading you get will seem low enough to be the problem: even if it isn't. The resistance of a transformer is just the wire in the windings: pretty low. What gives it impedance is the fact that it is inductive, and that works only with AC.

My point is to bear this in mind when you are poking around and not allow it to mislead you. I suppose it would be handy to have an inductance meter in these circumstances, but that's pretty rare as hobbyist equipment goes...

Here's a thought: The ST-800 has a funky line cord connection which I have never seen on any other device in the known Universe. When the cord gets lost it is common for people to cobble in the socket that accepts an IEC style cord (the kind you plug a computer in with, for example...). There is nothing wrong with doing this, but it doesn't mean that the people who do it have the slightest idea which wire goes where (...or why).

Do your machines have the original connector (three round pins) or a new one (three rectangular pins)?

--------------------
All I ask is a wide screen and a projector to light her by...

| IP: Logged

frank arnstein
Jedi Master Film Handler

Posts: 534
From: Gold Coast. Australia
Registered: Jan 2005

posted February 15, 2011 01:38 AM

Can anyone here help me get a copy of an owners manual for the Elmo ST 800 ? Perhaps Doug knows where. I can't see a manuals link anywhere.

dogtor [Confused]

Ok Now thanks.... Found a manual here at Projector Heaven.... [Razz]

[ February 16, 2011, 12:45 AM: Message edited by: frank arnstein ]

--------------------
At Projector Heaven the Focus is always on Detail.

____
[o:/o]<|=- dogtor@projectorheaven.com.au
//``\\
-----------------------------------------------

| IP: Logged

Steve Klare
Film Guy

Posts: 7016
From: Long Island, NY, USA
Registered: Jun 2003

posted February 15, 2011 08:02 AM

Frank,

For some reason I've never been able to figure out the ST-800 is less common than a lot of the other Elmos, so documentation like manuals and schematics is just as unusual. (There are legends of an ST-800MO for magnetic/optical playback, but I've never seen one. There's probably one in a cave somewhere, right next to the Holy Grail and the Ark of the Covenant.)

I don't think this scarcity is because of the machine itself. I really like mine. It's more basic than the ST-1200HD or the GSs, but it puts up a great picture and sound.

I think it's closest to the ST-600/ST-180 in design and shares a lot of parts.

I have the manual. When I have some quiet time in about two weeks I will scan it and offer it to the manuals section.

[ February 15, 2011, 09:19 AM: Message edited by: Steve Klare ]

--------------------
All I ask is a wide screen and a projector to light her by...

| IP: Logged

Daniel Florence
Junior
Posts: 13
From: Lyon, France
Registered: Jan 2010

posted February 15, 2011 02:11 PM

Steve, my ST800s with fuse trouble are both magnetic/optical ! (but no holy Grail, sorry...).

| IP: Logged

Steve Klare
Film Guy

Posts: 7016
From: Long Island, NY, USA
Registered: Jun 2003

posted February 15, 2011 06:00 PM

That's interesting...

Let's get back to the port the line cord plugs into. As described above, do you think it's the original?

--------------------
All I ask is a wide screen and a projector to light her by...

| IP: Logged

Daniel Florence
Junior
Posts: 13
From: Lyon, France
Registered: Jan 2010

posted February 16, 2011 11:32 AM

I have the new connector, it's the original one.

| IP: Logged

Winbert Hutahaean
Film God

Posts: 5468
From: Nouméa, New Caledonia
Registered: Jun 2003

posted February 16, 2011 11:42 AM

Daniel, can you post a photo of your ST-800 MO... as I never seen ones.

--------------------
Winbert

| IP: Logged

All times are Central

Printer-friendly view of this topic

UBB.classic^TM 6.3.1.2