Ontario-wide voltage reduction test happening Thursday, July 18

[rypalmer]

Possibly of interest to EV drivers in Ontario, there is an upcoming voltage reduction test planned by the Independent Electricity System Operator (IESO). The test will take place on Thursday, July 18, 2019 and involves two province-wide voltage reduction exercises:

- 3% voltage reduction from 10:00 a.m. to 11:00 a.m.
- 5% voltage reduction from 2:00 p.m. to 3:00 p.m.

Some equipment may be sensitive to voltage reductions. It is important to understand these impacts during a planned test in order to prepare for an actual emergency event and consider how a voltage reduction might affect escalators, elevators, sensitive electronic equipment, AND electric vehicles! I predict some voltage drop will cause charge rates to taper, for those who are actively charging during this test.

The purpose of these tests are to:
- Identify any equipment problems during this voltage reduction test
- Measure the total amount of attainable load reduction

Under provincial rules, the IESO is required to conduct regular tests of its emergency procedures in order to help ensure staff familiarity, and to identify and address any deficiencies. Voltage reduction tests are usually scheduled every 18 months and most recent system-wide test was performed on March 6, 2018.

For more information please visit the IESO website at Ensuring A Reliable Grid.

 

[Casmium]

Chernobyl started with a test

 

[sandpiper]

Possibly of interest to EV drivers in Ontario, there is an upcoming voltage reduction test planned by the Independent Electricity System Operator (IESO). The test will take place on Thursday, July 18, 2019 and involves two province-wide voltage reduction exercises:

- 3% voltage reduction from 10:00 a.m. to 11:00 a.m.
- 5% voltage reduction from 2:00 p.m. to 3:00 p.m.

Some equipment may be sensitive to voltage reductions. It is important to understand these impacts during a planned test in order to prepare for an actual emergency event and consider how a voltage reduction might affect escalators, elevators, sensitive electronic equipment, AND electric vehicles! I predict some voltage drop will cause charge rates to taper, for those who are actively charging during this test.

The purpose of these tests are to:
- Identify any equipment problems during this voltage reduction test
- Measure the total amount of attainable load reduction

Under provincial rules, the IESO is required to conduct regular tests of its emergency procedures in order to help ensure staff familiarity, and to identify and address any deficiencies. Voltage reduction tests are usually scheduled every 18 months and most recent system-wide test was performed on March 6, 2018.

For more information please visit the IESO website at Ensuring A Reliable Grid.

It will have no effect if you're hooked up to 240. I have a charger hooked up to 208V at my workplace and it's fine. Obviously it charges a bit slowing that it does at proper 240.

 

[brkaus]

If the voltage reduction happens while it is charging it may detect it as a fault and stop charging or reduce current.

Unplugging, setting the current back up, and plugging back it should allow it to charge regularly (although perhaps a bit slower) again.

 

[bijan]

I'm getting 30A at 191-192V right now at work. Wonder if anything will happen when they drop the voltage to 185-ish at 10am.

 

[brkaus]

I'm getting 30A at 191-192V right now at work. Wonder if anything will happen when they drop the voltage to 185-ish at 10am.

July 18

 

[bijan]

July 18

Oops! I'll keep an eye on it next week

 

[Blu-Ion]

Chernobyl started with a test

Graphite anodes in batteries will explode!!

 

[sandpiper]

It will have no effect if you're hooked up to 240. I have a charger hooked up to 208V at my workplace and it's fine. Obviously it charges a bit slowing that it does at proper 240.

I don't understand how it's possible to disagree with a fact. I do have it hooked up to 208V and it works fine. So if you have a charge hooked up to 240, a 3-5% reduction isn't less than 208. So... it will be fine. If it looks for rapid voltage drops, and triggers a fault, then I suppose it could require a restart. But doubt that that would happen.

 

[rypalmer]

I don't understand how it's possible to disagree with a fact. I do have it hooked up to 208V and it works fine. So if you have a charge hooked up to 240, a 3-5% reduction isn't less than 208. So... it will be fine. If it looks for rapid voltage drops, and triggers a fault, then I suppose it could require a restart. But doubt that that would happen.

You have no way of calling your statement a "fact". The way Tesla safeguards the wiring to the car is by ramping up charge rate and comparing the initial no-load voltage with the loaded voltage, which inevitably includes some voltage drop. The more voltage drop, the more conservative the car will get. But it all depends on the initial no-load voltage: everybody already knows Teslas charge at 208v just fine, 15% less than split phase 240v. And if this voltage drop happens suddenly, during a charging session, the car will throttle the charge rate. It's almost a guarantee in my view. My guess on this is that a 5% voltage drop may stop charging altogether. Tesla does this because of prior fires caused by loose connections in outlets and EVSE, and they detect these using voltage drop.

 

[sandpiper]

You have no way of calling your statement a "fact". The way Tesla safeguards the wiring to the car is by ramping up charge rate and comparing the initial no-load voltage with the loaded voltage, which inevitably includes some voltage drop. The more voltage drop, the more conservative the car will get. But it all depends on the initial no-load voltage: everybody already knows Teslas charge at 208v just fine, 15% less than split phase 240v. And if this voltage drop happens suddenly, during a charging session, the car will throttle the charge rate. It's almost a guarantee in my view. My guess on this is that a 5% voltage drop may stop charging altogether. Tesla does this because of prior fires caused by loose connections in outlets and EVSE, and they detect these using voltage drop.

It's an actual fact that I have a charger hooked up to 208 - so the 5% voltage drop from 240 means nothing other than the obvious drop in charging rate. Could a rapid drop cause it to fault out? Maybe.... I certainly do not know for a fact that it won't. But, I think you're speculating. I haven't put a logger on my feed but in the pre-LED lighting days, I saw lots of flickering/dimming of incandescent lights during storms and such. I see no reason to think that it's any better now. I just can't see it. And I've never had my charger mysteriously fault out.

But, I may be proven wrong. It may melt down to a puddle of plastic and copper.

 

[brkaus]

I hope lots of people have their cars plugged in when this test is done. For scientific studies...

 

[rypalmer]

Could a rapid drop cause it to fault out?

Yes! This is exactly what the car is looking for. To me a 5% voltage drop during charging would be unprecedented, but we shall see. For science.

 

[I am 3LECTRIC]

I'd prefer not to have my car plugged in for scientific studies, but I am traveling that morning and my Model 3 will be plugged in at Toronto Pearson during both tests

 

[Moonlit knight]

Basically, provincal brown outs? Maybe someone California has info on the effect on charging.

 

[yuhong]

I'm getting 30A at 191-192V right now at work. Wonder if anything will happen when they drop the voltage to 185-ish at 10am.

Yea, 5% is already a 10V drop I think

 

[Tz00]

I'm getting 30A at 191-192V right now at work. Wonder if anything will happen when they drop the voltage to 185-ish at 10am.

Yea, 5% is already a 10V drop I think

Don't forget.... with the correct adapter, from TT-30 to 14-50, the car will receive ~120V when the Tesla adapter was designed for ~240V. The car will charge fine with no issues.

The car does not care what the voltage is other than it needs to be between 85V and 265V, only a sudden voltage drop would be an issue, where the car thinks there is a fault. And a 5% voltage drop is not really that much. Voltage swings a fair amount hour-by-hour.

So in theory, a 240V system with a 64% voltage drop, the car will still charge, since the voltage is over the minimum 85V. So long as it doesn't drop there in an instant, there will be no issues.

 

[yuhong]

Don't forget.... with the correct adapter, from TT-30 to 14-50, the car will receive ~120V when the Tesla adapter was designed for ~240V. The car will charge fine with no issues.

The car does not care what the voltage is other than it needs to be between 85V and 265V, only a sudden voltage drop would be an issue, where the car thinks there is a fault. And a 5% voltage drop is not really that much. Voltage swings a fair amount hour-by-hour.

So in theory, a 240V system with a 64% voltage drop, the car will still charge, since the voltage is over the minimum 85V. So long as it doesn't drop there in an instant, there will be no issues.

I think the minimum for Tesla Model 3 used to be 108V, but I hope they have changed it by now.

 

[Bill25cycle]

Possibly of interest to EV drivers in Ontario, there is an upcoming voltage reduction test planned by the Independent Electricity System Operator (IESO). The test will take place on Thursday, July 18, 2019 and involves two province-wide voltage reduction exercises:

- 3% voltage reduction from 10:00 a.m. to 11:00 a.m.
- 5% voltage reduction from 2:00 p.m. to 3:00 p.m.

Some equipment may be sensitive to voltage reductions. It is important to understand these impacts during a planned test in order to prepare for an actual emergency event and consider how a voltage reduction might affect escalators, elevators, sensitive electronic equipment, AND electric vehicles! I predict some voltage drop will cause charge rates to taper, for those who are actively charging during this test.

The purpose of these tests are to:
- Identify any equipment problems during this voltage reduction test
- Measure the total amount of attainable load reduction

Under provincial rules, the IESO is required to conduct regular tests of its emergency procedures in order to help ensure staff familiarity, and to identify and address any deficiencies. Voltage reduction tests are usually scheduled every 18 months and most recent system-wide test was performed on March 6, 2018.

For more information please visit the IESO website at Ensuring A Reliable Grid.

3% and 5% drops are mild. My house is in a neighborhood with 'third-world' electricity. In fact, it is worse than 3rd world. My voltage varies from 255 when the solar panels are running flat out, to my all time record low of 188 volts at the service entrance (94/188) during mid august last year.

THERE ARE FIVE BIG REASONS why the juice in my neighborhood is so lousy - all due to National Grid Incompetence. If there is any interest - i'll delineate them but I won't mention them since they are technical and it would bore most here. And no, it is not an issue of bad splices. My main concern is that the voltage doesn't drop enough to damage the several refrigerators and freezer. The central AC is not a problem since It can run at 197 volts in Arizona and it doesn't get that hot in Buffalo , New York to worry about it.



My old Roadster, if using the $1500 UMC alarmed at 207 volts and would shut down at 200. Good thing I'm at a nominal 240 and not a nominal 208, since businesses adjoining my neighborhood would be 94Y/163 - and I don't think there is ANY car that can run that low - even the 25 kw BOSCH single phase CCS unit ($8800) requires a minimum of 170. My Volt EVSE requires at least 99 volts to run. I remember the cord that came with the Roadster would run down to 103 volts IF the current was reduced from 15 amperes to 12.

 

[yuhong]

3% and 5% drops are mild. My house is in a neighborhood with 'third-world' electricity. In fact, it is worse than 3rd world. My voltage varies from 255 when the solar panels are running flat out, to my all time record low of 188 volts at the service entrance (94/188) during mid august last year.

THERE ARE FIVE BIG REASONS why the juice in my neighborhood is so lousy - all due to National Grid Incompetence. If there is any interest - i'll delineate them but I won't mention them since they are technical and it would bore most here. And no, it is not an issue of bad splices. My main concern is that the voltage doesn't drop enough to damage the several refrigerators and freezer. The central AC is not a problem since It can run at 197 volts in Arizona and it doesn't get that hot in Buffalo , New York to worry about it.



My old Roadster, if using the $1500 UMC alarmed at 207 volts and would shut down at 200. Good thing I'm at a nominal 240 and not a nominal 208, since businesses adjoining my neighborhood would be 94Y/163 - and I don't think there is ANY car that can run that low - even the 25 kw BOSCH single phase CCS unit ($8800) requires a minimum of 170. My Volt EVSE requires at least 99 volts to run. I remember the cord that came with the Roadster would run down to 103 volts IF the current was reduced from 15 amperes to 12.

Note that 100V is commonly used in Japan. And commercial three phase services are typically off a different transformer.