Cheaper way to install services to fulfill outside safety switch

[don_resqcapt19]

It's a non insignificant extra cost, and visually quite a bit more intrusive. I don't see what the problem was with pulling a meter.

Have you ever seen the socket come apart when pulling a meter? It is a very dangerous operation to pull a meter and even more so if there is load. Fire fighters are not trained to pull meters and do not have the ability to open the main to reduce the load before pulling it and in many area the response of the utility is 30 to 60 minutes.

I just wonder why this rule only applies to one and two family dwellings? In my opinion an outside means of disconnect is even more important to first responders for the larger and higher voltage services used for commercial and industrial occupancies, and ones where pulling the meter does not disconnect any power to the building.

 

[don_resqcapt19]

What is so hard about pulling a meter? do you really think the power company people who set meters are highly experienced and highly trained? What is there to know? Seems like 15 minutes of training is all that is required. They already have face Shields and gloves. These guys go into burning buildings but they can't pull a meter?? why is everyone overthinking this so much?

It is not hard...it is just extremely unsafe and pulling a live meter is not something that should ever be done
Firefighters equipment is not rated for arc flash energy. There are major differences in the construction of arc flash rated PPE and firefighter turn out gear.

 

[shortcircuit2]

Dwelling has a 200-amp service with the utility meter outside and the 200-amp main breaker panel inside...SEU 3-wire between outside meter and inside main breaker service equipment.

Now the electrical contractor adds a generator with a SUSE rated 200-amp transfer switch and the installation is arranged according to 230.85(3) with the SUSE rated transfer switch outside adjacent to the meter, with 3-wire SEU load side connected from the SUSE rated 200-amp transfer switch into the existing 200-amp main breaker service equipment inside and Marks the SUSE rated transfer switch with a label according to 230.85(3), EMERGENCY DISCONNECT-NOT SERVICE EQUIPMENT.

This is Code compliant under the 2020 NEC per section 230.82(10) and 230.85(3)

Now when utility power is out and the system runs on generator you have 4-wire Feeder from the generator feeding a 3-wire arranged system.

Now a solar contractor comes and adds a Supply-Side connected PV Interactive System with an ESS that can operate as a Hybrid System. Again connected per 230.82(6) and 230.85(3) and Marks the SUSE rated 690.13 PV System Disconnecting Means with a label according to 230.85(3), EMERGENCY DISCONNECT-NOT SERVICE EQUIPMENT. The system is wired from the Supply-Side connection to the PV System Disconnect with another 3-wire arrangement.

This Dwelling wiring arrangement will have multiple system bonds per 250.24(A)(4), at the existing Service Equipment, the generator transfer switch and the PV System Disconnect. There is still only 1-Service to the Dwelling, but with multiple system bonds required by Code, but against the intent of 250.24(A)(5) creating multiple paths for unbalanced system current and fault current.

I do not consider this a safe arrangement. There should be only 1-system bonding jumper with a 4-wire arrangement (grounded conductor and equipment grounding conductor separate) downstream to all other system interconnections.

You don't see an issue with this?

 

[romex jockey]

I honestly forget how many redundant disco's the '20 has now....genny's......PV's......

so maybe one big E stop might be a cheaper 'compliance'

~RJ~

 

[jaggedben]

Dwelling has a 200-amp service with the utility meter outside and the 200-amp main breaker panel inside...SEU 3-wire between outside meter and inside main breaker service equipment.

Now the electrical contractor adds a generator with a SUSE rated 200-amp transfer switch and the installation is arranged according to 230.85(3) with the SUSE rated transfer switch outside adjacent to the meter, with 3-wire SEU load side connected from the SUSE rated 200-amp transfer switch into the existing 200-amp main breaker service equipment inside and Marks the SUSE rated transfer switch with a label according to 230.85(3), EMERGENCY DISCONNECT-NOT SERVICE EQUIPMENT.

This is Code compliant under the 2020 NEC per section 230.82(10) and 230.85(3)

Now when utility power is out and the system runs on generator you have 4-wire Feeder from the generator feeding a 3-wire arranged system.

Now a solar contractor comes and adds a Supply-Side connected PV Interactive System with an ESS that can operate as a Hybrid System. Again connected per 230.82(6) and 230.85(3) and Marks the SUSE rated 690.13 PV System Disconnecting Means with a label according to 230.85(3), EMERGENCY DISCONNECT-NOT SERVICE EQUIPMENT. The system is wired from the Supply-Side connection to the PV System Disconnect with another 3-wire arrangement.

This Dwelling wiring arrangement will have multiple system bonds per 250.24(A)(4), at the existing Service Equipment, the generator transfer switch and the PV System Disconnect. There is still only 1-Service to the Dwelling, but with multiple system bonds required by Code, but against the intent of 250.24(A)(5) creating multiple paths for unbalanced system current and fault current.

I do not consider this a safe arrangement. There should be only 1-system bonding jumper with a 4-wire arrangement (grounded conductor and equipment grounding conductor separate) downstream to all other system interconnections.

You don't see an issue with this?

Honestly the only problem I see is objectionable current, which was already prohibited before 230.85 existed. And the other stuff was permitted before 230.85, too. So I don't really get what you're driving at. Multiple MBJs for multiple service disconnect has always been permitted.

 

[electrofelon]

Have you ever seen the socket come apart when pulling a meter?

No, I've been doing this for 20 years, and we pull meters here all the time. I have not seen that.

It is a very dangerous operation to pull a meter and even more so if there is load. Fire fighters are not trained to pull meters and do not have the ability to open the main to reduce the load before pulling it and in many area the response of the utility is 30 to 60 minutes.

I just wonder why this rule only applies to one and two family dwellings? In my opinion an outside means of disconnect is even more important to first responders for the larger and higher voltage services used for commercial and industrial occupancies, and ones where pulling the meter does not disconnect any power to the building.

It is not hard...it is just extremely unsafe and pulling a live meter is not something that should ever be done
Firefighters equipment is not rated for arc flash energy. There are major differences in the construction of arc flash rated PPE and firefighter turn out gear.

We are not going to agree here. I don't think it's dangerous at all. Fault currents for resi are almost always very low, and it is generally accepted that 240v will not sustain an arc. Typically firefighter equipment is plenty. Again, I am curious about this extensive training and PPE POCO meter setters use...... LOL.

 

[ptonsparky]

I missed seeing one come apart by inches. I happened to look at the connections before I pulled it.

 

[Fred B]

No, I've been doing this for 20 years, and we pull meters here all the time. I have not seen that.




We are not going to agree here. I don't think it's dangerous at all. Fault currents for resi are almost always very low, and it is generally accepted that 240v will not sustain an arc. Typically firefighter equipment is plenty. Again, I am curious about this extensive training and PPE POCO meter setters use...... LOL.

Seen one the back connection on meter stayed on the meter pan. The meter essentially split in two front/rear. There was severe corrosion on the meter terminals.

AFA Fault current on residential, maintaing an arc is mostly true but the concern under load conditions is for an arc flash, that is indeed possible on residential level currents. POCO will even gear up with arc flash PPE when they set or pull a meter, unless power disconnected at the pole. Also most new meter panels around here POCO is requiring "ringless" thus opening and exposing live conductors is neccessary to remove the meter, also enhancing the ability for any arc flash formed to escape the enclosure.

Side mention as to maintaining an arc, maybe not an arc as you would say like in the dramatic illustrations, but arcing none the less, had one a contractor cut through a live 240 for a heater that didn't trip the breaker that arced and burned up the rope in a dramatic firework like display about 20ft, until someone got to the panel and shut entire panel down. Conductor or terminal spacing key for ability to maintaining an arc, but 240 residential will under correct conditions maintain an arc. How "dangerous" the arc level is, well? What is approach boundary for residential 240V?