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CANADA VOLTAGE SYSTEM
- Thread starter raadhatab
- Start date
That's quite a general question. Canada shares the North American 60Hz frequency and voltage levels are 120/240/208/600/4160/6900/13800VAC with limited use of 480V.
Grounding can be solid or through a grounding resistor depending on fault levels and protection schemes.
Grounding can be solid or through a grounding resistor depending on fault levels and protection schemes.
The Canadian Electrical Code:
8-100 Current calculations
When calculating currents that will result from loads, expressed in watts or volt amperes, to be supplied by a low-voltage ac system, the voltage divisors to be used shall be 120, 208, 240,277, 347, 416, 480, or 600 as applicable.
Grounding
If grounding will result in a maximum voltage to ground not exceeding 150 volts the system must be grounded.
If the system incorporates a neutral conductor it shall be grounded.
This implies solidly grounded.
The grounding method or lack of it for other installations is an engineering decision.
In British Columbia lighting circuits of 277 volts and 347 volts are common in other than residential installations.
The trend in B.C. has been away from 480 volts to 600 volts in new installations.
However there are many legacy 480 volt systems. 480 volt motors transformers and other equipment are readily available.
In many areas it is difficult to secure a 480 volt service from the Utility. However I have seen 600:480 volt auto-transformers interposed between a 600 volt supply and a Motor Control Center to supply a large amout of legacy 480 volt equipment.
A plant that was operating on 480 volts was moved to a new location and the utility would not supply 480 volts in the new location. At that time, a kiosk containing service entrance equipment, a metering section, a 600 volt MCC, an auto-transformer section, and a 480 volt MCC was available as a factory built, approved assembly.
With primary metering and customer transformers, 480 volts is common.
I understand that in and around Ontario 600 volts is the common industrial voltage and that 480 volt systems are rare.
Many years ago, 440 was the common voltage in the west. This was migrated to 480 volts with the same 460 volt rated motors applied.
Simiklarly in the east, 550 volts was at one time the standard and this was migrated to 600 volts with the same 550 volt motors being applied.
respectfully
8-100 Current calculations
When calculating currents that will result from loads, expressed in watts or volt amperes, to be supplied by a low-voltage ac system, the voltage divisors to be used shall be 120, 208, 240,277, 347, 416, 480, or 600 as applicable.
Grounding
If grounding will result in a maximum voltage to ground not exceeding 150 volts the system must be grounded.
If the system incorporates a neutral conductor it shall be grounded.
This implies solidly grounded.
The grounding method or lack of it for other installations is an engineering decision.
In British Columbia lighting circuits of 277 volts and 347 volts are common in other than residential installations.
The trend in B.C. has been away from 480 volts to 600 volts in new installations.
However there are many legacy 480 volt systems. 480 volt motors transformers and other equipment are readily available.
In many areas it is difficult to secure a 480 volt service from the Utility. However I have seen 600:480 volt auto-transformers interposed between a 600 volt supply and a Motor Control Center to supply a large amout of legacy 480 volt equipment.
A plant that was operating on 480 volts was moved to a new location and the utility would not supply 480 volts in the new location. At that time, a kiosk containing service entrance equipment, a metering section, a 600 volt MCC, an auto-transformer section, and a 480 volt MCC was available as a factory built, approved assembly.
With primary metering and customer transformers, 480 volts is common.
I understand that in and around Ontario 600 volts is the common industrial voltage and that 480 volt systems are rare.
Many years ago, 440 was the common voltage in the west. This was migrated to 480 volts with the same 460 volt rated motors applied.
Simiklarly in the east, 550 volts was at one time the standard and this was migrated to 600 volts with the same 550 volt motors being applied.
respectfully
waross,
Is that because a lot of the mill equipment in existing BC mills (built more than 10 years ago) came from US mills that were shut down in the late '70s and early '80s? That was the prevailing rumor in Washington when I was working there. I never got a good opinion from a Canadian on that issue. The one's who thought it to be true were generally people who were too young to have paid attention to things like that at the time it would have happened.
Is that because a lot of the mill equipment in existing BC mills (built more than 10 years ago) came from US mills that were shut down in the late '70s and early '80s? That was the prevailing rumor in Washington when I was working there. I never got a good opinion from a Canadian on that issue. The one's who thought it to be true were generally people who were too young to have paid attention to things like that at the time it would have happened.
- Thread starter
- #5
Thanks for your answers, my understanding that the phase tom earth voltages used are 120,240,277 & 347 which actually will obtain 208,416,480 &600volt respectively via phase to phase voltages. If so what's behind that? and why all these voltage varieties are used for? and how are they obtained ?is it by transformer tap changing ?or specific transformers for each voltage?
Regards
Regards
raadhatab;
There are specific transformers for each voltage. For 120/208 volt systems, the two 120 volt windings in a normal distribution transformer are reconnected in parallel instead of in series. There are also three phase transformers with only 120 volt windings, connected in star for the 208 volts.
jraef;
No. The legacy voltage dating back probably to the 30's or earlier, judging by some of the old mills I worked in years ago, was 440 volt delta. This migrated to 277/480 volt wye.
Actually much of the equipment in the Washington mills may have originated in Western Canada. The province of British Columbia is a world leader in the design and manufacture of sawmill machinery and automation equipment. The first 'Chip'N'Edger" was developed as a joint venture between Eburne sawmill in Vancouver Canada and a manufacturer of sawmill equipment. When I worked there in the early 70's the first prototype "Chip'N'Edger" was still in service.
The voltage was 440 delta.
Most of the DC machines had been salvaged from a decommisioned WW2 warship.
Respectfully
There are specific transformers for each voltage. For 120/208 volt systems, the two 120 volt windings in a normal distribution transformer are reconnected in parallel instead of in series. There are also three phase transformers with only 120 volt windings, connected in star for the 208 volts.
jraef;
No. The legacy voltage dating back probably to the 30's or earlier, judging by some of the old mills I worked in years ago, was 440 volt delta. This migrated to 277/480 volt wye.
Actually much of the equipment in the Washington mills may have originated in Western Canada. The province of British Columbia is a world leader in the design and manufacture of sawmill machinery and automation equipment. The first 'Chip'N'Edger" was developed as a joint venture between Eburne sawmill in Vancouver Canada and a manufacturer of sawmill equipment. When I worked there in the early 70's the first prototype "Chip'N'Edger" was still in service.
The voltage was 440 delta.
Most of the DC machines had been salvaged from a decommisioned WW2 warship.
Respectfully
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