Legacy Enersave Systems - Power Conditioners

[rguimond]

Not necessarily a PLC question, but it certainly applies to power management systems...

Has anyone worked in a facility where their power conditioning devices have been installed? I witnessed a demonstration last week where power consumption (VA)to a 1/4 Hp motor was reduced from 485VA to 130VA (at the meter) by simply connecting what they call a "linear" device in parallel with the load. There was an immediate reduction in the heat dissipation from the motor (it was running around 120F before the device was brought on-line and quickly dropped to under 90F and was still dropping when the demonstration ended).

If someone had presented this data to me, I would have handed it back and told him not to waste my time, but it's tough to argue with an actual demonstration.

 

[rdrast]

Sounds like snake oil.

Anyway, 1/4 HP = 485 VA?!!!! Damn... I'd get a new motor.

 

[rguimond]

Snake Oil was my first reaction. However, when I swapped the plug-in power use meters around, I got the same results. The guy doing the demo even stripped the covering off the cabtire to bare single conductors so I could verify with a clamp-on.

The readings I took are attached.

Anyway, I've arranged for a demo of a 30Hp 3-phase device this Thursday with my meters and will post the results...

 

[leitmotif]

I do not like the math as presented

119 volt X 4 amp = 476 watt = 476 VA
NOT ...............129 and 487 as shown in table
CAPACITOR BANK

Something is goofy with their instrumentation. I would trust these guys and their product about half as far as I could throw them.

With motors power in = power out + inefficiency
1/4 HP in = 1/4 HP out.

Dan Bentler

 

[rguimond]

Typo WRT "1.49". Should have been "4.19"

However...

My electrician and I just got through a demonstration with the sales rep. We tested a device on a 20 Hp hydraulic power pack and a 40 Hp discus compressor unit. Results are attached.

Just to be clear, current readings were taken at the line side of the local disconnect (I - DISCONNECT) and at the load side of the starter (I -MOTOR). The device was connected at the load side of the starter. No more than 36" of cable between disconnect and starter, in both cases.

Loading of the hydraulic pump was accomplished by cranking down the pressure relief valve until 10% more current than nameplate current (20A) was being drawn (20+10%=22A).

The refrigeration compressor could not be unloaded, so there is only one set of numbers.

As you can see, there is a considerable decrease in metered current with the device attached. It's tough to argue with the numbers.

Apparently, the device is some type of "harmonic filter".

 

[OkiePC]

Have a look here:

http://ths.gardenweb.com/forums/load/wiring/msg0821554329789.html?163

Is a KVAR device what you are dealing with?

 

[rguimond]

Not 100% sure.

http://www.energyautomation.com/

Device is simple. Silver cannister with three leads, plus a ground connector.

 

[OkiePC]

Yep. Looks like the same deal. I would expect a very small savings, but only if your utility provider will reward you for improved power factor. I could be wrong, and it will depend on how much of an improvement you can actually make, and what the rates and measurement methods used by your electric company.

 

[rguimond]

Worth investigating, for sure. I'll keep the group posted.

 

[theDave2]

A motor running unloaded has a lower PF than a loaded motor.

From their website FAQ:

If we already have Power Factor Correction, can we still experience energy costs savings?

Absolutely. We address your facility's power quality and electrical distribution losses. Normally, power factor correction is conducted at your main distribution panel, which doesn’t improve your electrical efficiency or deal with power quality issues. Energy Automation Systems Inc. (EASI)deals with equipment, air-conditioning, refrigeration, and lighting losses. We will save you money regardless of power factor correction at the main.

So they don't have any device to sell if you already have PF correction.

rguimond: Did you use a clamp-on amp probe or use a device that also reads the voltage at the same time ? See https://www.ohiosemitronics.com/default.asp , they make power meters.

 

[rguimond]

Used clamp-on ammeter and checked voltages from L1, L2 & L3 to ground. Voltage didn't really change - maybe half a volt or so, so i didn't bother to include them in the chart.

BTW, I have capacitor bank @ distribution panel. Power factor in the plant ranges from 0.96 to 0.92 about 95% of the time. Sometimes drops as low as 0.9 for brief periods of time.

I spoke with my electrical utility this afternoon about these devices. Some of their engineers have witnessed similar tests and have visited sites where they have been installed recently. Appartenly, a local saw mill has improved power factor to 0.98 from 0.8 and usage has dropped nearly 12%. They're excited because the devices could be used to counteract the effect heat pumps are having on residential distribution - no demand charges on residential customers in my area, since there was no real need to when most loads were resistive.