Yet another Liftmaster 3800 question...

[jgira12]

My door raising height is limited by the cable tension device location. There is a metal rail bracket that is in the way of placing the unit any closer to the top of the door. I know I could cut a section out of the bracket, but I would rather just do away with the tension device....the manual states this piece is mandatory, but maybe you know how to defeat it. The 3rd pic shows the difference in door height between the old chain drive unit and the jackshaft unit.

 

[Daves75]

it looks like you notched out the wood ,so I will assume the spacing there is very tight. May not be as pretty, but can you mount this on the right hand side of the door, inside looking out up closer to the drum?
That should give you the correct spacing required, so you do not activate the switch.

 

[Kapt]

I deactivated my cable tensioner and it works fine. It's basically a switch that needs to stay closed for the motor to operate. If you take apart the tension device you will find a very small circuit board with a switch soldered into it. I unsoldered the switch and soldered in a jumper wire in place of it.

It's been a while since I did mine, but if you need further clarification or pics, let me know.

 

[jgira12]

I deactivated my cable tensioner and it works fine. It's basically a switch that needs to stay closed for the motor to operate. If you take apart the tension device you will find a very small circuit board with a switch soldered into it. I unsoldered the switch and soldered in a jumper wire in place of it.

It's been a while since I did mine, but if you need further clarification or pics, let me know.

Man, that's what I was hoping for. Yes, I would like additional info...please post here, or email me at [email protected]

 

[jgira12]

it looks like you notched out the wood ,so I will assume the spacing there is very tight. May not be as pretty, but can you mount this on the right hand side of the door, inside looking out up closer to the drum?
That should give you the correct spacing required, so you do not activate the switch.

thanks for the suggestion, but no can do because the same galvanized bracket interferes there too (RH)...same as shown in the pics of the LH side.

 

[70rsss]

The cable tensioner needs to be above the door just under the pully. Move the switch spool to the other side and you will get full travel. just make sure you mount it high enough that the door doesn't hit the switch body on the way up.....like i did before I moved it up another inch. lol

 

[Daves75]

thanks for the suggestion, but no can do because the same galvanized bracket interferes there too (RH)...same as shown in the pics of the LH side.

I'm sorry I should have been more specific, I meant on the RH side inside the track below the torsion tube. You can defeat this switch as said above, but it is there for a reason. It is a little differant then the photo eyes, this is there to insure the cables or door has not slacked. This opener could cause more problems if they are, plus it is a secondary safety feature.

Option two the " roller on this switch used to be able to be un-pinned and switched to the other side, which means you could mount it the same way as mentioned above. either should take care of the issue.

By the way nice vette.

 

[Kapt]

Man, that's what I was hoping for. Yes, I would like additional info...please post here, or email me at [email protected]

Check your email.

 

[PurdueSD]

I'm sorry but you guys kill me...

You've got the switch mounted no where near its the correct spot and its causing issues.... so you want to disable it.

I mean, im no osha smuck. I have the laser eyes bypassed on a couple doors, but youre opening up a whole new can of worms. You do realize if your cables slack the moter keeps turning, so you skip a drum and your door is coming all the way to the ground and fast. All it takes is a broom handle upright under the door one time. Hope you or someone else is no where near it.

Goodluck.

 

[Kapt]

I'm sorry but you guys kill me...

You've got the switch mounted no where near its the correct spot and its causing issues.... so you want to disable it.

I mean, im no osha smuck. I have the laser eyes bypassed on a couple doors, but youre opening up a whole new can of worms. You do realize if your cables slack the moter keeps turning, so you skip a drum and your door is coming all the way to the ground and fast. All it takes is a broom handle upright under the door one time. Hope you or someone else is no where near it.

Goodluck.

I see your point, but what about a standard opener that doesn't attach to the torque tube? They don't have cable slack devices. Is there a design feature that prevents this from happening?

 

[jgira12]

My doors have been up for 8 years...an 8' and a 17' wide. What could cause this sudden slack condition? I maintain them well, and besides, we are talking about the 8' door only which weighs less than half of the 17' door. My kids are long gone and I am the only one using the 8' door for the vette.....and like he said, the chain drive opener doesn't have/need a tension monitor, and that's on the monster 17 footer. I think this is a case of some authority somewhere fantasizing about some event that occurs once in a million, then handcuffing an entire industry with 'belt and suspenders' pseudo solutions. I bet Liftmaster would like to delete this extra burden, but have no choice in the matter.

 

[jgira12]

I'm sorry I should have been more specific, I meant on the RH side inside the track below the torsion tube. You can defeat this switch as said above, but it is there for a reason. It is a little differant then the photo eyes, this is there to insure the cables or door has not slacked. This opener could cause more problems if they are, plus it is a secondary safety feature.

Option two the " roller on this switch used to be able to be un-pinned and switched to the other side, which means you could mount it the same way as mentioned above. either should take care of the issue.

By the way nice vette.

Thanks Dave. Yes, I took another look and maybe there is enough room to allow it to squeeze in there. When I first looked where to mount it I could swear the door would rip it off the wall it is so tight on that side, so I followed directions and put it where it is...the saga continues

 

[PurdueSD]

I see your point, but what about a standard opener that doesn't attach to the torque tube? They don't have cable slack devices. Is there a design feature that prevents this from happening?

The door is physically attached to the opener on a standard chain/ belt/ screw operator. If the chain breaks the weight of the door is still balanced by the torsion springs. If the door is balanced correctly when installed, it wont come crashing to the ground.

My doors have been up for 8 years...an 8' and a 17' wide. What could cause this sudden slack condition? I maintain them well, and besides, we are talking about the 8' door only which weighs less than half of the 17' door. My kids are long gone and I am the only one using the 8' door for the vette.....and like he said, the chain drive opener doesn't have/need a tension monitor, and that's on the monster 17 footer. I think this is a case of some authority somewhere fantasizing about some event that occurs once in a million, then handcuffing an entire industry with 'belt and suspenders' pseudo solutions. I bet Liftmaster would like to delete this extra burden, but have no choice in the matter.

Hah, did you even read what i wrote... A broom handle under one side of the door for example. all it takes is for one side of the door to get cocked a little bit causing slack in the other sides cable. Then the cable jumps the drum while the operator continues turning the shaft. WHy do you think commercial jackshaft doors use reversing edges?

I agree with you on one thing... safety features are over used on many pieces of equipment. This isn't one of them.