I have an energy management company installing fan relays on exhaust fans in schools. They are using RIB relays and class 2 wiring back to a network based controller to shut off exhaust fans after hours to conserve energy. They are mixing class 2 wiring and electric light and power in the same raceways and enclosures, and claiming they are exempt from NEC rules because the state exempts temperature control contractors from licensing and inspections. They are installing 1/2 HP rated relays on 120 V circuits, which have multiple motors/exhaust fans. They are not checking the HP ratings on the motors on the circuit. I have told them that the HP rating is for individual motors based on the locked rotor current. They are trying to claim that the relays are rated for 20 amps, and as long as its "not tripping the breaker" they are ok with what they are doing.They are also using double pole RIB relays and putting two separate circuits derived from two separate panelboards and two separate OCD to control two separate motors.Obviously they don't have a clue what they are doing. Anyone else have a problem with these types of "energy management contractors"? We are talking a big company here that is nationwide and their Project Manager claimed to me that nobody has ever taken them to task before. I'm just a concerned electrical QC person working in a big (60+ schools) school district. When somebody boasts they are doing this type of work all over my state and the US and nobody has ever complained in his "15 years with the company", it really makes me wonder.
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Motor controllers/energy management
- Thread starter dshurt
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Re: Motor controllers/energy management
Lessee if I got this strait
1. YOu are an employee of the school district
2. Your job is to ensure QC of electrical
3. QC in this case to me includes NEC, good design, reliability, ease of use, kid proof.
If they are not doing a good job for you (even IF it is NEC compliant) then change it.
If you tell me I been doing this for 15 years and no one complained I have alarm bells going off.
Dan Bentler
Lessee if I got this strait
1. YOu are an employee of the school district
2. Your job is to ensure QC of electrical
3. QC in this case to me includes NEC, good design, reliability, ease of use, kid proof.
If they are not doing a good job for you (even IF it is NEC compliant) then change it.
If you tell me I been doing this for 15 years and no one complained I have alarm bells going off.
Dan Bentler
pierre
Senior Member
- Location
- Westchester County, New York
Re: Motor controllers/energy management
This company is twisting the inspection process with the Code requirements. This is usually done to confuse the consumer and make their job easy -which translates into ...how can we make more money on an installation.
"90.2 Scope.
(A) Covered. This Code covers the installation of electric conductors, electric equipment, signaling and communications conductors and equipment, and fiber optic cables and raceways for the following:
(1) Public and private premises, including buildings, structures, mobile homes, recreational vehicles, and floating buildings
(2) Yards, lots, parking lots, carnivals, and industrial substations
FPN: For additional information concerning such installations in an industrial or multibuilding complex, see ANSI C2-1997, National Electrical Safety Code.
(3) Installations of conductors and equipment that connect to the supply of electricity
(4) Installations used by the electric utility, such as office buildings, warehouses, garages, machine shops, and recreational buildings, that are not an integral part of a generating plant, substation, or control center.
Pay particular attention to # 1... PUBLIC and PRIVATE PREMISES, ...... (this includes public and private schools...you may not require inspections, but still have to follow codes)
This company is twisting the inspection process with the Code requirements. This is usually done to confuse the consumer and make their job easy -which translates into ...how can we make more money on an installation.
"90.2 Scope.
(A) Covered. This Code covers the installation of electric conductors, electric equipment, signaling and communications conductors and equipment, and fiber optic cables and raceways for the following:
(1) Public and private premises, including buildings, structures, mobile homes, recreational vehicles, and floating buildings
(2) Yards, lots, parking lots, carnivals, and industrial substations
FPN: For additional information concerning such installations in an industrial or multibuilding complex, see ANSI C2-1997, National Electrical Safety Code.
(3) Installations of conductors and equipment that connect to the supply of electricity
(4) Installations used by the electric utility, such as office buildings, warehouses, garages, machine shops, and recreational buildings, that are not an integral part of a generating plant, substation, or control center.
Pay particular attention to # 1... PUBLIC and PRIVATE PREMISES, ...... (this includes public and private schools...you may not require inspections, but still have to follow codes)
Re: Motor controllers/energy management
By The Way, RIB relays are Relay in a Box. The RIB relays in question are the type that has both the low volt and the high in the same 1/2 threaded hub that goes into the junction box. They are great for class 1 control wiring in an enclosure where you can mix the high and low volt. They are impossible to use in a 4 square box with class 2 wiring and still maintain the NEC required 0.25 inch separation from the associated high and low volt. Energy management contractor in question was not familiar with class 2 rated RIB relays, which keeps the class 2 connections outside the j-box. The NEC uses the words protection from "fire initiation" and the potential from accidental "shock" in its definition of why we have such strigent rules for class 2 wiring. Saving energy is a good thing, as long as you know what you're doing when installing energy saving ideas!
By The Way, RIB relays are Relay in a Box. The RIB relays in question are the type that has both the low volt and the high in the same 1/2 threaded hub that goes into the junction box. They are great for class 1 control wiring in an enclosure where you can mix the high and low volt. They are impossible to use in a 4 square box with class 2 wiring and still maintain the NEC required 0.25 inch separation from the associated high and low volt. Energy management contractor in question was not familiar with class 2 rated RIB relays, which keeps the class 2 connections outside the j-box. The NEC uses the words protection from "fire initiation" and the potential from accidental "shock" in its definition of why we have such strigent rules for class 2 wiring. Saving energy is a good thing, as long as you know what you're doing when installing energy saving ideas!
Re: Motor controllers/energy management
this does not sound nec compliant. even if there is no state law, didnt the contractor have so sign a contract.
I work on US military installations. These facilities are exempt from state and local laws, but the contracts clearly state, that work will be done in compliance with the NEC, and other state and local codes. Thus voiding any such presumed exemption.
Check with your lawyers, I doubt that they let such a huge loophole be left in the contract.
this does not sound nec compliant. even if there is no state law, didnt the contractor have so sign a contract.
I work on US military installations. These facilities are exempt from state and local laws, but the contracts clearly state, that work will be done in compliance with the NEC, and other state and local codes. Thus voiding any such presumed exemption.
Check with your lawyers, I doubt that they let such a huge loophole be left in the contract.
Re: Motor controllers/energy management
Dan,
Yes, I am changing it. Just started the QCing with this type of contractor in our buildings.
Generally they do just stick to scheduling, commissioning, sequencing, etc. of environmental control equipment. Now they are moving into areas like Power Factor Correction penalties from utility company, shedding (exhaust fan)loads, etc. to save energy money.
For big electrical items they use sub-contracted electrical contractors. That has not been the case with the fan relays, and I think the reason for the confusion between environmental controls and electrical work requiring adherence to the NEC.
Dan,
Yes, I am changing it. Just started the QCing with this type of contractor in our buildings.
Generally they do just stick to scheduling, commissioning, sequencing, etc. of environmental control equipment. Now they are moving into areas like Power Factor Correction penalties from utility company, shedding (exhaust fan)loads, etc. to save energy money.
For big electrical items they use sub-contracted electrical contractors. That has not been the case with the fan relays, and I think the reason for the confusion between environmental controls and electrical work requiring adherence to the NEC.
Re: Motor controllers/energy management
JB,
That's a good point about that type of RIB. But I still think if you adhere to the NEC, it is not possible for this reason: The low volt class 2 conductors and high volt wires come out of the same threaded hub of the relay. You could change the class 2 to a class 1 wiring per the NEC and use this relay. Functional Devices, which now offers a class 2 RIB relay, must have recognized this problem. With this type of RIB relay you do not need to put the class 2 wiring in the same enclosure.The contractor I am working with is looking into changing their class 2 power source to class 1. I would think the most economical way to do this job, would be to use the right RIB relay in this type of installation.
JB,
That's a good point about that type of RIB. But I still think if you adhere to the NEC, it is not possible for this reason: The low volt class 2 conductors and high volt wires come out of the same threaded hub of the relay. You could change the class 2 to a class 1 wiring per the NEC and use this relay. Functional Devices, which now offers a class 2 RIB relay, must have recognized this problem. With this type of RIB relay you do not need to put the class 2 wiring in the same enclosure.The contractor I am working with is looking into changing their class 2 power source to class 1. I would think the most economical way to do this job, would be to use the right RIB relay in this type of installation.
Re: Motor controllers/energy management
JB,
By the way, there is a contract. The contractor in question is very responsive to my concerns. I think the things I have mentioned were honest mistakes. Everyone I'm dealing with recognizes the need to stick to the NEC requirements when doing electrical work. Red flags went up for me, when someone says they having doing it this way for years, and nobody has ever questioned their work before. I wonder how many other "energy management" contractors in general are making the same assumptions and mistakes.
JB,
By the way, there is a contract. The contractor in question is very responsive to my concerns. I think the things I have mentioned were honest mistakes. Everyone I'm dealing with recognizes the need to stick to the NEC requirements when doing electrical work. Red flags went up for me, when someone says they having doing it this way for years, and nobody has ever questioned their work before. I wonder how many other "energy management" contractors in general are making the same assumptions and mistakes.
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