- Location
- Wisconsin
- Occupation
- PE (Retired) - Power Systems
Very few breakers contain energized "electromagnets" (some exceptions are dual-magnetic design and those with undervoltage release).
Line load tester
- Thread starter Matt Blum
- Start date
- Status
Matt Blum
Member
- Location
- Allentown, PA
I just checked out the manual at they're website and indeed does state it has the ELL feature.
Much Thanks!
Much Thanks!
gar
Senior Member
- Location
- Ann Arbor, Michigan
- Occupation
- EE
081125-2137 EST
wptski:
What is a definition for ELL and what is the theory behind this function?
If I have a given circuit designed for a 20 A breaker, and instead I put in a 5 A breaker how does this instrument detect the difference between the two breakers? Did they provide any technical explanation?
I have been very busy the last 2 months and have not answered your question on power quality yet. I was called on an electrical problem and in turn there were very many mechanical problems. This was at one of your competitors and also a supplier. This probably identifies the company for you.
Relative to the gear box tear down all the bearings were shot and everything was saturated with fine metal chips. I have not been able to get any information on what or where the failure in the electric clutch was.
.
wptski:
What is a definition for ELL and what is the theory behind this function?
If I have a given circuit designed for a 20 A breaker, and instead I put in a 5 A breaker how does this instrument detect the difference between the two breakers? Did they provide any technical explanation?
I have been very busy the last 2 months and have not answered your question on power quality yet. I was called on an electrical problem and in turn there were very many mechanical problems. This was at one of your competitors and also a supplier. This probably identifies the company for you.
Relative to the gear box tear down all the bearings were shot and everything was saturated with fine metal chips. I have not been able to get any information on what or where the failure in the electric clutch was.
.
wptski
Senior Member
- Location
- Warren, MI
gar:
It's "Estimated Load on Line". I had made contact with a engineer at Ideal and he mentioned the new feature, sent me a draft of the instructions but didn't explain how it works at all. They hardly give away secrets!:grin:
I'll take a look at what he sent and PM you if there's anything in there about how it works but I don't think that there is.
gar
Senior Member
- Location
- Ann Arbor, Michigan
- Occupation
- EE
081126-1953 EST
wptski:
Thank you for the PM with the Ideal description. It is well written an does adequately describe what is the function.
This ELL function estimates the amount of load (current) in the neutral on a circuit from a test performed by plugging into an outlet. No need to directly access the wiring. Thus, one does not need to open a main panel to get access to the circuit neutral.
The ELL function does not tell you the capability of a circuit.
It can help identify harmonic problems on a neutral. It is an approximation and it greatest accuracy results when plugged into the same outlet as the load. Its results degrade as you move to an outlet further from the main panel compared to the location of the load.
Their description describes the limitations, or sources of error.
How does it work? The Ideal instrument has the capability to measure the impedance of the neutral conductor from the main panel to the Ideal instrument. Also has the ability to measure the voltage drop across the neutral from the main panel to the ideal instrument. Knowing the impedance and this voltage it can calculate the current from the load. Basically the neutral becomes the shunt for measuring the current. If the Ideal is further away from the main panel than the load, then it will use a higher impedance than that which is common to the load and thus an error. The same kind of error does not exist if the Ideal is between the main panel and the load. However, now the accuracy of measuring the impedance may degrade.
Should be a useful instrument to look for high neutral currents.
It might be useful to others if you put the information from Ideal here in this thread.
.
wptski:
Thank you for the PM with the Ideal description. It is well written an does adequately describe what is the function.
This ELL function estimates the amount of load (current) in the neutral on a circuit from a test performed by plugging into an outlet. No need to directly access the wiring. Thus, one does not need to open a main panel to get access to the circuit neutral.
The ELL function does not tell you the capability of a circuit.
It can help identify harmonic problems on a neutral. It is an approximation and it greatest accuracy results when plugged into the same outlet as the load. Its results degrade as you move to an outlet further from the main panel compared to the location of the load.
Their description describes the limitations, or sources of error.
How does it work? The Ideal instrument has the capability to measure the impedance of the neutral conductor from the main panel to the Ideal instrument. Also has the ability to measure the voltage drop across the neutral from the main panel to the ideal instrument. Knowing the impedance and this voltage it can calculate the current from the load. Basically the neutral becomes the shunt for measuring the current. If the Ideal is further away from the main panel than the load, then it will use a higher impedance than that which is common to the load and thus an error. The same kind of error does not exist if the Ideal is between the main panel and the load. However, now the accuracy of measuring the impedance may degrade.
Should be a useful instrument to look for high neutral currents.
It might be useful to others if you put the information from Ideal here in this thread.
.
wptski
Senior Member
- Location
- Warren, MI
gar:
Okay, the following is from the email I received from Ideal. I didn't ask, they just mentioned the new feature going into the two Suretest models.
Instruction for use of Estimated Load on Line
The IDEAL SureTest models 61-164 and 61-165 have now incorporated an Estimated Load on Line (ELL) feature. This function allows the user to quickly obtain a general idea of the total current load drawn on the branch circuit. The proprietary way in which these calculations are made allows the user to plug the unit into an outlet and measure current load on that branch circuit.
Best accuracy can be obtained by becoming familiar with the operation of the load on line test. The distance of the SureTest from the load will affect accuracy. Try to position the SureTest close to the largest load on line.
For best accuracy, power up all loads and make certain they are working at their normal rate of operation, then plug the SureTest into an appropriate
nearby outlet on the same circuit. The Load on Line will be very close to
the actual load. The maximum current measured is held in the small display at the top right hand corner. This value will be held until the Sure Test is removed from the outlet.
While you may do so, the accuracy will suffer if loads are turned on and off during the test period. To quickly confirm a questionable reading, remove the SureTest and reinsert it to recalculate with all loads running.
Due to the proprietary method used to calculate the load, variations in the line and neutral resistance can cause significant variations to the accuracy of the displayed current. Ideally, there should be less than 5% Vd and less than 0.25 Ohms of resistance. In cirical applications, it is recommended that a traditional current clamp such as the Ideal Model 61-746 be used at the panel to obtain a very accurate current measurement.
ESTIMATED LOAD ON LINE.
The estimated load on line (ELL) is limited to a maximum reading of 15 amps, to best reflect actual conditions on the line as the data is monitored. The Peak Hold display will monitor the load as long as the SureTest is plugged into the outlet. It indicates an estimate of the maximum load on that circuit over time. The calculation is based on the
peak current flowing in the neutral conductor. Neutral current is the
result of powered equipment on the line. The ELL will also help indicate circuits that are overloaded, and those that have a common neutral. This is especially important when the circuit being measured powers single phase switching power supplies, like computers. The third harmonic generated by this equipment is not cancelled, and returns on the neutral, causing overload and heating of the neutral conductor. This is particularly true in 3 phase 4 wire panels, (120/208) where third harmonic is very common. The test allows determination of the remaining capacity of the circuit. It can also help determine whether or not the circuit is dedicated, since a circuit with no load will have very low or zero neutral to ground voltage. Any reading over 1 amp indicates the circuit is very likely not dedicated.
The load on line is strictly an estimate. This is an indirect reading, so there may be significant error in the reported values.
The SureTest does not have to be in the furthest outlet on the branch circuit. Accuracy will decrease significantly with distance. Worst accuracy will result when the load is between the SureTest and the distribution panel.
To get the very best results, the SureTest should be plugged into the same outlet as the load, with no other loads on line.
Remember that shared neutrals will indicate the current flowing from both hot wires. If the ground wire is carrying current, there will be significant error introduced, and this is a dangerous situation that should be rectified immediately.
Okay, the following is from the email I received from Ideal. I didn't ask, they just mentioned the new feature going into the two Suretest models.
Instruction for use of Estimated Load on Line
The IDEAL SureTest models 61-164 and 61-165 have now incorporated an Estimated Load on Line (ELL) feature. This function allows the user to quickly obtain a general idea of the total current load drawn on the branch circuit. The proprietary way in which these calculations are made allows the user to plug the unit into an outlet and measure current load on that branch circuit.
Best accuracy can be obtained by becoming familiar with the operation of the load on line test. The distance of the SureTest from the load will affect accuracy. Try to position the SureTest close to the largest load on line.
For best accuracy, power up all loads and make certain they are working at their normal rate of operation, then plug the SureTest into an appropriate
nearby outlet on the same circuit. The Load on Line will be very close to
the actual load. The maximum current measured is held in the small display at the top right hand corner. This value will be held until the Sure Test is removed from the outlet.
While you may do so, the accuracy will suffer if loads are turned on and off during the test period. To quickly confirm a questionable reading, remove the SureTest and reinsert it to recalculate with all loads running.
Due to the proprietary method used to calculate the load, variations in the line and neutral resistance can cause significant variations to the accuracy of the displayed current. Ideally, there should be less than 5% Vd and less than 0.25 Ohms of resistance. In cirical applications, it is recommended that a traditional current clamp such as the Ideal Model 61-746 be used at the panel to obtain a very accurate current measurement.
ESTIMATED LOAD ON LINE.
The estimated load on line (ELL) is limited to a maximum reading of 15 amps, to best reflect actual conditions on the line as the data is monitored. The Peak Hold display will monitor the load as long as the SureTest is plugged into the outlet. It indicates an estimate of the maximum load on that circuit over time. The calculation is based on the
peak current flowing in the neutral conductor. Neutral current is the
result of powered equipment on the line. The ELL will also help indicate circuits that are overloaded, and those that have a common neutral. This is especially important when the circuit being measured powers single phase switching power supplies, like computers. The third harmonic generated by this equipment is not cancelled, and returns on the neutral, causing overload and heating of the neutral conductor. This is particularly true in 3 phase 4 wire panels, (120/208) where third harmonic is very common. The test allows determination of the remaining capacity of the circuit. It can also help determine whether or not the circuit is dedicated, since a circuit with no load will have very low or zero neutral to ground voltage. Any reading over 1 amp indicates the circuit is very likely not dedicated.
The load on line is strictly an estimate. This is an indirect reading, so there may be significant error in the reported values.
The SureTest does not have to be in the furthest outlet on the branch circuit. Accuracy will decrease significantly with distance. Worst accuracy will result when the load is between the SureTest and the distribution panel.
To get the very best results, the SureTest should be plugged into the same outlet as the load, with no other loads on line.
Remember that shared neutrals will indicate the current flowing from both hot wires. If the ground wire is carrying current, there will be significant error introduced, and this is a dangerous situation that should be rectified immediately.
ramsy
NoFixNoPay Electric
- Location
- LA basin, CA
- Occupation
- Service Electrician 2020 NEC
This is not a new feature. Its an old feature, recycled.
The "Estimated Load on Line" (ELL) feature existed on ShureTest Model ST-1THD, made by Industrial Commercial Electronics, since 1996, before this original patent holder sold out to Ideal.
The engineer's press release provide to you was lifted directly from the original manual, Model ST-1THD Digital Wireing/Haronic Analyzer. Made in USA by: Industrial Commercial Electronics, Inc. 2421 Harlem Road Buffalo, NY 14225. (c) 1997. 37pgs
Ideal removed PF=(Power Factor) and Ld=(Watts) from all future production models, but kept the ELL=(amps) feature with Ideal's ShureTest 61-152/3 model numbers.
Fulthrotl
~Autocorrect is My Worst Enema.~
- Occupation
- E
yep. what he said.
there isn't any other way to do it. you are measuring flow, not pressure.
pressure can be measured anywhere, flow has to be measured at the
point of peak flow.... the breaker.
wptski
Senior Member
- Location
- Warren, MI
It's new to the 61-164/165 SureTest, correct? I had asked if there was anything done yet to fix the issue of the SureTest tripping a GFCI during the G impedance test which was supposed to be looked at. This ELL info was given to me then. The SureTest is normally is disliked by the majority in this forum.
Thanks for the history of the feature.
Fulthrotl
~Autocorrect is My Worst Enema.~
- Occupation
- E
i'm thrilled....
i just bought a 61-165 this week, and it is old stock, and doesn't have
the new feature.
after reading a bit however, on multiwire circuits, the feature has some
limitations, so it's usefulness to me is limited.... so i'll quit whining now...
wptski
Senior Member
- Location
- Warren, MI
I don't really know when they planned to start adding the feature. The manual is downloadable from Ideal's site, if it was added, it should be in there or maybe mentioned someother way.i'm thrilled....
i just bought a 61-165 this week, and it is old stock, and doesn't have
the new feature.
after reading a bit however, on multiwire circuits, the feature has some
limitations, so it's usefulness to me is limited.... so i'll quit whining now...
wptski
Senior Member
- Location
- Warren, MI
The manual at Ideal's site shows no ELL included yet, so maybe it isn't yet.i'm thrilled....
i just bought a 61-165 this week, and it is old stock, and doesn't have
the new feature.
after reading a bit however, on multiwire circuits, the feature has some
limitations, so it's usefulness to me is limited.... so i'll quit whining now...
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