Equipment Disconnect Height

[ramIII]

We have a couple of insta hot water heaters installed at a bank in the mechanical room that were mounted at about six feet above the floor. We installed the disconnects for them directly above them. The inspector has failed us because the disconnect handle is higher than 6'7''. My contention is that they are mounted adjacent to the equipment so the 6'7'' does not apply. Any thoughts.

 

[JDBrown]

You certainly seem to be covered under 404.8(A) Exception No. 2. Have you tried arguing the point with the Inspector?

 

[GoldDigger]

We have a couple of insta hot water heaters installed at a bank in the mechanical room that were mounted at about six feet above the floor. We installed the disconnects for them directly above them. The inspector has failed us because the disconnect handle is higher than 6'7''. My contention is that they are mounted adjacent to the equipment so the 6'7'' does not apply. Any thoughts.

No such exception in the code unless there are other disconnects in series which are both low enough and accessible. Is that the case for you?

 

[ramIII]

I did argue 404.8(A) exception No. 2. His response was that since the equipment was mounted at below 6'7" that the disconnect should be also. The space in the room is tight and the piping for the insta hots is below them. We would have to build a mounting rack in front of the pipes to lower them below the insta hots.

 

[Dennis Alwon]

I did argue 404.8(A) exception No. 2. His response was that since the equipment was mounted at below 6'7" that the disconnect should be also. The space in the room is tight and the piping for the insta hots is below them. We would have to build a mounting rack in front of the pipes to lower them below the insta hots.

He may have a valid argument.

 

[JDBrown]

I did argue 404.8(A) exception No. 2. His response was that since the equipment was mounted at below 6'7" that the disconnect should be also. The space in the room is tight and the piping for the insta hots is below them. We would have to build a mounting rack in front of the pipes to lower them below the insta hots.

Based on just the strict wording of the Code I would agree with you, even though I agree with the Inspector's logic. When I looked up the section, I was very surprised that there was no caveat in Exception No. 2 stating that it only applies if the motor/appliance/other equipment is installed above 6'7", or something to that effect. Since the Code doesn't say that, if I were the Inspector I would probably grudgingly approve the installation, and then immediately start writing up a code change proposal.

Unfortunately for you, I'm not the Inspector. In my (admittedly limited) experience, what the Inspector wants, the Inspector gets. You might be able to appeal to his supervisor or file a variance, but those things take time, and while you wait your customer doesn't have hot water.

 

[jumper]

He may have a valid argument.

Why, just because he is right?

 

[ramIII]

Based on just the strict wording of the Code I would agree with you, even though I agree with the Inspector's logic. When I looked up the section, I was very surprised that there was no caveat in Exception No. 2 stating that it only applies if the motor/appliance/other equipment is installed above 6'7", or something to that effect. Since the Code doesn't say that, if I were the Inspector I would probably grudgingly approve the installation, and then immediately start writing up a code change proposal.

Unfortunately for you, I'm not the Inspector. In my (admittedly limited) experience, what the Inspector wants, the Inspector gets. You might be able to appeal to his supervisor or file a variance, but those things take time, and while you wait your customer doesn't have hot water.

The inspector has agreed to let his boss make the final ruling. My thought is that if there were some sort of height limitation it should be addressed in the code. The other part of this is that we can build the rack below to meet the the inspectors interpretation of the code but when one goes bad in 5 years and the same model is not available and the plumber has to rework the piping the owner is probably also paying an electrician to rework the disconnects.

 

[JDBrown]

He may have a valid argument.

Why, just because he is right?

This response interests me because, while I agree with the Inspector in principle (if the equipment isn't above 6'7", then the switch shouldn't be), I don't think the Code supports his opinion.

404.8 Accessibility and Grouping.
(A) Location. All switches and circuit breakers used as switches shall be located so that they may be operated from a readily accessible place. They shall be installed such that the center of the grip of the operating handle of the switch or circuit breaker, when in its highest position, is not more than 2.0 m (6 ft 7 in.) above the floor or working platform.
...
Exception No. 2: Switches and circuit breakers installed adjacent to motors, appliances, or other equipment that they supply shall be permitted to be located higher than 2.0 m (6 ft 7 in.) and to be accessible by portable means.

Where does it say that the switch can only be above 6'7" if the equipment is also? It seems logical, but the Code doesn't actually say it (in this section, anyway).

 

[GoldDigger]

Why, just because he is right?

No, because the Code is unclear.
BTW, when the Code is unclear having a valid argument is not identical to being right. But when EC and Inspector both have valid arguments, guess who wins?

 

[eHunter]

Just build a raised non-conductive platform in front of the panel.

 

[GoldDigger]

Just build a raised non-conductive platform in front of the panel.

Extending out for the full required working space, of course.

 

[jumper]

No, because the Code is unclear.
BTW, when the Code is unclear having a valid argument is not identical to being right. But when EC and Inspector both have valid arguments, guess who wins?

The code says that the disco/switch can be over 6'7" if the equipment is. The switch has to be under 6'.7' in most cases, not the equipment. The exceptions.

The switch can be at 5" and the equipment at 12', no?

 

[Jraef]

I had to get into this years ago because the rule USED to be 6'8" a long time ago, the 6'7" was a change as the result of a NIOSH study in the mid 1970s showing that to be the maximum reach of a woman that was 5' tall, the low side of average height at that time. In the late 1970s, I worked for US Steel and our Allen Bradley MCCs had been designed in 1971, BEFORE the change, so the center of the top most handle in a Size 1 starter bucket plugged into the top space in a section that had a floor sill installed ended up at 6'7-1/2" above the floor, slightly below the old standard but slightly above the new one. We couldn't change it, so A-B came up with a little clip-on handle extension that dropped down to allow that 5' person to reach it. Total PITA but the rules gods were satisfied.

Back then we used to call Exception 2 the "Trapeze Rule", because it supposedly came about as a result of trapeze mounted transformers in factories with equipment drops that were nowhere near columns so there would be nowhere for the disconnect to be mounted that would be in clear site of the transformer. The argument went that since it was FOR that transformer, you would ALREADY be required to get on a ladder ("portable means") to service the transformer, so there was no need to require that the disconnect be lower. The basic concept was that when the equipment that the disconnect was feeding was higher than the 6'7" rule, it was OK for the disconnect to be adjacent.

One potential argument to explore by the way is to bring up 422.31(B) where it says that the service disconnect means can be the panel branch circuit breaker. If it were a motor, 430.107 allows that only ONE of the disconnect means must be accessible, and I have successfully argued that putting a padlock clip on the panelboard breaker satisfied that, so then the switch on the inaccessible equipment just becomes the local equipment disconnect and is OK even without Exception 2. You would be stretching the 430.107 issue because yours is not a motor, but I would bring it up as an example in defense of the concept. Those little padlock clips are often a cheap solution for stuff like this.

 

[kwired]

I had to get into this years ago because the rule USED to be 6'8" a long time ago, the 6'7" was a change as the result of a NIOSH study in the mid 1970s showing that to be the maximum reach of a woman that was 5' tall, the low side of average height at that time. In the late 1970s, I worked for US Steel and our Allen Bradley MCCs had been designed in 1971, BEFORE the change, so the center of the top most handle in a Size 1 starter bucket plugged into the top space in a section that had a floor sill installed ended up at 6'7-1/2" above the floor, slightly below the old standard but slightly above the new one. We couldn't change it, so A-B came up with a little clip-on handle extension that dropped down to allow that 5' person to reach it. Total PITA but the rules gods were satisfied.

Back then we used to call Exception 2 the "Trapeze Rule", because it supposedly came about as a result of trapeze mounted transformers in factories with equipment drops that were nowhere near columns so there would be nowhere for the disconnect to be mounted that would be in clear site of the transformer. The argument went that since it was FOR that transformer, you would ALREADY be required to get on a ladder ("portable means") to service the transformer, so there was no need to require that the disconnect be lower. The basic concept was that when the equipment that the disconnect was feeding was higher than the 6'7" rule, it was OK for the disconnect to be adjacent.

One potential argument to explore by the way is to bring up 422.31(B) where it says that the service disconnect means can be the panel branch circuit breaker. If it were a motor, 430.107 allows that only ONE of the disconnect means must be accessible, and I have successfully argued that putting a padlock clip on the panelboard breaker satisfied that, so then the switch on the inaccessible equipment just becomes the local equipment disconnect and is OK even without Exception 2. You would be stretching the 430.107 issue because yours is not a motor, but I would bring it up as an example in defense of the concept. Those little padlock clips are often a cheap solution for stuff like this.

I don't know what the height was way back but it was 6' 6" from at least mid 80's to 1999 or maybe 2002. Then NEC changed it to 6' 7", which is about as close as you can get with no fractional inches to an even 2.0 meters, and likely the reason for the change.

 

[GoldDigger]

This response interests me because, while I agree with the Inspector in principle (if the equipment isn't above 6'7", then the switch shouldn't be), I don't think the Code supports his opinion.

Where does it say that the switch can only be above 6'7" if the equipment is also? It seems logical, but the Code doesn't actually say it (in this section, anyway).

Adjacent can be horizontally or vertically, so we explore some specific statements:
A. If any part of the equipment is below 6'7", the control can be adjacent to the part that is below 6'7", and therefore cannot itself be above 6'7" using the exception.
B. If any part of the equipment is above 6'7", the control may be adjacent to (even adjacent above) that part.
C. If putting the control adjacent to but immediately above the equipment locates the control itself above 6'7", it is not allowed.
D. If putting the control adjacent to but immediately above the equipment locates the control itself above 6'7", it is allowed.
E. Considering adjacent very liberally to count horizontal distance only, the control can be at any height above or below the equipment, without restriction as long as part of it is within the vertical rectangle set by the width of the equipment plus a reasonable clearance.

Although none of them cover all possible situations, they are all arguable applications of that same Code wording to the OP's situation. Choose one.

 

[ramIII]

The inspector has agreed to let his boss make the final ruling. My thought is that if there were some sort of height limitation it should be addressed in the code. The other part of this is that we can build the rack below to meet the the inspectors interpretation of the code but when one goes bad in 5 years and the same model is not available and the plumber has to rework the piping the owner is probably also paying an electrician to rework the disconnects.

After discussing this with the building official he overuled the inspector. The bottom of the insta hots were at 6' and the top 7'1". The disconnects were mounted 4" above the insta hot. He agreed that this met the "adjacent to" exeption for the appliance. He also based his decision that if an average height person came to service the insta hots they would probably use a ladder anyway.

 

[GoldDigger]

He also based his decision that if an average height person came to service the insta hots they would probably use a ladder anyway.

Explicitly recognizing the "Trapeze rule" logic Jraef described.

 

[Gregg Harris]

I don't know what the height was way back but it was 6' 6" from at least mid 80's to 1999 or maybe 2002. Then NEC changed it to 6' 7", which is about as close as you can get with no fractional inches to an even 2.0 meters, and likely the reason for the change.

Changed to 6' 7" in 1996 was 380-8

 

[jumper]

We have a couple of insta hot water heaters installed at a bank in the mechanical room that were mounted at about six feet above the floor. We installed the disconnects for them directly above them. The inspector has failed us because the disconnect handle is higher than 6'7''. My contention is that they are mounted adjacent to the equipment so the 6'7'' does not apply. Any thoughts.

Yep, I still need to read questions/posts more closely before replying.:slaphead:

What you wrote and what I "read" are two way different things, the error being on my part.:ashamed1: