B&h 70hr motor plug?

ishan vernallis · May 21, 2007

Hi-

I just recieved an old B&H 70hr

that came with a motor

which has an XLR power connector,

but no normal A.C. wall plug attached.

It's a simple enough job.

but this is my first time dealing with an XLR

on a camera motor rather than on a mic.

Is there a standard for what prong is positive

and which is negative?

No.1 postive?

No.2 negative?

No.3 ground?

I don't want to risk hooking it up wrong

and frying the motor.

thanks ever so much!

ishan

l

Edited May 21, 2007 by ishan vernallis

Charles MacDonald · May 22, 2007

I just recieved an old B&H 70hr
that came with a motor

which has an XLR power connector,

but no normal A.C. wall plug attached.

Most of the b&h motors are 110-115V AC. Check the nameplate.

The one I am trying to get working does not have any ground pin, just the two sides of the AC line on two pins.

(the problem I have is the connector is 180 degrees out from an XLR3 Mike conector, and si I have been unable to find the mating plug- If anyone knows were to buy one, I am all ears.)

IF your power cord just has loose ends, and the XLR plug fits, and the nameplate says 110v Ac-Dc. you probaly have two wires which can connect to the AC . If one wire is White , connect that to the silver screw in the plug,.

There are only two screws that hold the connector on the side of the motor, so it is easy to open it up and see the connectons, and at the same time be sure the wore is not frayed. be careful not to drop the little shims that hold the connector away from the round part of the motor.

If you have a friend who plays with electronics, you might try it first with a variac and an isolation transformer. You DO want to be sure thet the line is not shorted to the case.

ishan vernallis · May 22, 2007

Thanks Charles!

Yes, I am glad that at least the camera came with an on/off switched xlr plug

that fits nicely into the silver xlr mount.

I opened the xlr conector mount (which is a cannon?)

and saw that you were correct there is no ground,

but there also was no difference between the two wires,

both black, one going to prong no.1, the other going to no.2.

rather than saying 110v Ac-Dc, the nameplate reads 12 volts dc 8 amps.

the guy I got the camera from on ebay said that the motor have tested

running from a car battery.

maybe this would be a good way to test which wire is positive and negative

with out giving it a full 110 jolt?

another thing I am also curious about these motors...

it says it runs 8-64 fps (which is why i got it, to shoot 64fps)

but i don't see any clearly marked knob or screw

to adjust f.p.s...?

do you just adjust the f.p.s. setting on the camera

and then the motor speed is regulated by that?

seems like there must be a regulator on the motor.

Clive Tobin · May 22, 2007

... the nameplate reads 12 volts dc 8 amps. ...

If the nameplate says 12 volts, DO NOT plug it directly into 120 !!!

This is probably a series wound motor which will actually work on AC or on either polarity of DC, with perhaps not as high a speed available on AC. It is characteristic of this type motor that it will run as fast as it can, depending on loading, such as in a vacuum cleaner. So the speed is controlled only by the camera governor. The motor power is chosen by the designer so that it will not quite burn out the governor in typical use with the design voltage applied.

ishan vernallis · May 22, 2007

If the nameplate says 12 volts, DO NOT plug it directly into 120 !!!

Thanks for the warning Clive!

so I guess it's not as simple as going to radio shack

and putting a normal wall socket plug

on the xlr cable?

the name plate also says "cycles-DC"

what do i need to do to run this motor? :blink:

Edited May 22, 2007 by ishan vernallis

ishan vernallis · May 22, 2007

If I can not plug this motor into 120

does that mean that the motor is only to be used

with a battery pack?

or is there some sort of regulator/converter

that can make it possible to use it

from a wall socket?

thanks for the input!!!

ishan vernallis · May 22, 2007

I think I might have found the solution?

http://www.longvalleyequip.com/adapter.php

has any one ever used one of these?

Eric Dinger · May 22, 2007

You could go with one of those, or just make your own, it wouldn't be too hard. But it also wouldn't run very long, if the amp rating on the motor is right, it pulls 8 amps. Most of those batterys from drill are 2-3 Ah, so you could only run the camera for 15-20 minutes before having to recharge.

Could get some photos of the nameplate? I'm trying to build a filmo resource. Also if your interested in selling it, shoot me an email.

Eric Dinger · May 22, 2007

Hate to do a double post but it won't let me edit my other post.

If you go with the power tool battery adaptor, make sure you get one that uses 12v batteries, and don't use anyother voltage! It's important because of the way to motor works if you overspeed the motor you run the risk of damageing your motor and the governor in the camera.

How the Filmo motors work:

The Filmo motors run at a constant speed, there is a slip clutch built into the right angle drive (your data plate should list the torque required to make it slip, 7 in/lbs I think). You set the speed with the regular knob on the camera and the governor controls the speed. The slip clutch allows the excess speed of the motor to be dissipated, but it has to be in good working order. Make sure the drive housing has good (not hardened) grease in it.

ishan vernallis · May 22, 2007

thanks muchly eric!

here are the pics that the seller put up for the motor,

using these to save time.

yes, it is a 12 volt motor,

i spoke with doug at long valley,

and their dewalt adapters are 12 too.

the clutch -torque on the motor name plate

reads LBS 9-1...

thanks for clearifying that it is the cameras govenor

that regulates the speed, not the motor.

what i am wondering is if the dewalt rig will give the motor enough juice

to drive the camera at the full 64fps?

i have this earialist falling off the high wire scene

that kinda needs to be slo mo.

"Make sure the drive housing has good (not hardened) grease in it."

i guess i'll have to take this motor apart a bit

to see exactly what you're refering to...

i have a general understanding of such things,

once put an engine in a 72vw bus, can't be too different, right?

i don't want to sell the motor, would rather get the rig working, and shoot.

but i may be in portland early next month,

if you would like to take a look for the filmo resource?

Charles MacDonald · May 23, 2007

Hi, yes you hav a 12 volt unit all right. the 8 amps sounds about right. 12v @8 Amps is 96 watts. Mine is 110 V at .9 amps so it takes 99 watts. (mine is part# 031397 for reference)

Mine has the same gear ratio and speed range listed. The motor has a clutch that ships to avoid over torqueing the camera which is held to speed by the govener.

Goes to show that you should not count on us making assumptions without seeing the unit. You have a variant that I had not heard of before..

Chances are 50-50 that it does not depend on polarity. The ac-dc motors have the rotor in series with the field coil, and it is quite posible that the 12V version used the same general idea. You can probaly throw 12 volts at it both ways and confirm that the output shaft works the same way. Taking it appart for a cleaning would allow you to trace the circuit to be sure of that. If they used a permanant magnet then the reotaion would depend on the polarity. In fact it is quite posible that it can be used on 12V ac. That would take a heck of a big transformer. like a Hamond Power Transformers 185F12 which is about 40 dollars US in the Mouser catalog. if it really needs DC you would have to add a rectifier and posible a filter cap to that .

Drawing 8 amps you probaly want a heavy battery like a Lead acid jobbie. A car batery is typicaly 70 amp hour so with an 8 AMp load it would run for 8 hours. a 10 amp hoyr would run less than 2 hours

Eric Dinger · May 23, 2007

The slip clutch is under a round cover that's about 1 3/4" across on the right angle drive, it's held on by 3 screws (on mine anyways), not real hard to get to. Unfortently I don't know what the right kind of grease is, if yours needs to be replaced. I also wouldn't go around dissassembling anything inside the cover.

I'd like to get a look at it when you come through, get some better photos, if you don't mind.

I'll have photos of the cover and the slip clutch up latter tonight or tomorrow.

ishan vernallis · May 23, 2007

The slip clutch is under a round cover that's about 1 3/4" across on the right angle drive, it's held on by 3 screws (on mine anyways), not real hard to get to.

yep, i see the three screws, i thought that might be what you were talking about.

i'll open it in the morning and see how bad the lube looks.

I also wouldn't go around dissassembling anything inside the cover.

i hear that.

swapping out a motor is one thing,

rebuilding a tranny a nutter.

thanks so much charles, clive, and eric

i've learned quite a bit today!

Eric Dinger · May 23, 2007

Chris I would think that his motor would require DC. It seems like B&H labled things pretty well, I would even go so far as to say that it is a permenent magnet motor for that reason. Mine is a 115 volt model like yours, and it is labled for AC or DC operation.

Attached is a picture of the slip clutch and where it's located, this one seems to be greased well. You also can't check out how the motor is wired from here, and I don't recomend that you dissasemble the whole motor.

Edited May 23, 2007 by Eric Dinger

ishan vernallis · May 23, 2007

well, this is how my motor looks in the slip clutch compartment.

a bit different than yours.

it seems that your clutch doesnt have a cylnder around it

like mine does.

all of the grease in my clutch it outside of a metal cylnder

and there is no sign of any grease having ever been inside the actual clutch...?

the grease is a bit firm but not dry.

and the cylnder moves around with the whole clutch assembly when i turn the outer pully wheel.

i'm a bit hesitant to fill the assemble with grease if it doesn't look like there was any there before.

might make it slip too much, he he?

i repacked the grease since taking this photo and all of the cracks you see in the grease

easily smoothed out...

Eric Dinger · May 23, 2007

I don't know what to tell you, I've read that the clutch it self should be lubed, but that was only one source (the only source I could find).

It's interesting because the clutch torque is higher on your model as well.

You could try running it, but you may damage one of the gears beyond repair if the clutch doesn't slip, you could also try it by hand, get something about a foot long that fits in the slot on the end of the drive shaft (a flat head screwdriver works well) and pull gently. It may take a little bit of force at first if it's been sitting, but it shouldn't be more that a pound of force. Just to be clear your turning the screwdriver, not turning the motor on.

Your motor also doesn't have a int. duty rating does it?

Also about running it, you start/stop the camera with by interrupting the power to the motor, the shutter button should be locked to on and the spring motor wound all the way down.

In case anyone is wondering, I've seen part #'s for four different Filmo motors, the 12v dc one in this discussion, a 24v dc one, a 115 ac/dc one, and a 115 ac only one.

Edited May 23, 2007 by Eric Dinger

ishan vernallis · May 24, 2007

o.k.

so i spoke with the kinded hearted owner

@ MAGNA-TECH ELECTRONIC CO.

who sells and services filmo gear...

and he confirmed that the inner workings of the slip clutch

do need to be lubricated.

thanks eric for bringing my attention to this!

as i might have otherwise burned out the clutch

and it would be a crying shame to ruin a piece of history

due to lack of knowledge.

now just to find the right 12v 8 amp power supply

and make sure i have it spinning in the correct direction.

Edited May 24, 2007 by ishan vernallis

Eric Dinger · May 24, 2007

Well I can say that mine works just fine being lubed, so I guess it doesn't really matter as long as it still slips!

About the rotation, the inching knob on the motor should spin clockwise, which means the drive shaft should spin counter-clockwise when viewed straight on. at least it does on mine. I assume all filmos are the same.

Edited May 24, 2007 by Eric Dinger