Motor Saver Technical Book

8/2/2019 Motor Saver Technical Book

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MOTOR SAVER Technical Book

SK-hitech Co.,Ltd


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-CONTENTS-

1. Principle of Motor Saver

2. Truth of I 2 R (Line Loss)

3. Difference of Motor Saver and Capacitor Bank

4. Experimental Verification of Motor Saver Effect

5. Proper Installation Way of Motor Saver


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1. Principle of Motor Saver

New Concept of Compensation of Power Factor(the ratio of effective power toapparent power)

The diversified ways to improve the efficiency of electric system while to reducepower consumption have been developed and will be developed now and forever.However, it is hardly to find the groundbreaking the electric power reductionequipment likes Motor Saver that its main principle is Compensation of PowerFactor. Finally, we are able to reduce remarkably electric power consumptionboth for commercial and industrial with Motor Saver..

What is Power Factor

There are two kinds of electric power for the consumers.1. The electricity[electric power] consumed for carrying out the work2. The electricity[electric power] consumed for making of magnetic current

essential for the operation of inducible electric equipment.

The foregoing the electricity[electric power] stated in #2 is called to WattlessPower due to not using for the actual work.The typical examples are the inducible-load like motor or transformer that needs

more current-inflow in distribution line to maintain the stable output. Afterall power factor is calculated as the consumable electric power for the actualwork divided by total consumable power.Motor Saver carries out its role to improve power factor by cutting off

unnecessary inflow-current by supplying Wattless Power.

How does Motor Saver save the consumable money?

There are two types for Motor Saver to save money.

First, a electric company imposes a fine by the low power factor.From their point of view, the electric company should supply relatively moreunnecessary electric power to the customer charge of the low power factor and itmakes burden too heavy for the company. But in case of using Motor Saver, itcan reduce a fine of low power factor since power factor would be improved.Moreover, the electric charge is expected to be reduced by reducing of themaximum demanded electricity and volume of consumed electric power.

Second, the other benefit by using Motor Saver is the relative increase incapacity of the distribution line since Motor Saver reduce the volume of current-inflow to the line. Generally, hanging Motor Saver to the existed line, you can get

20% surplus current to supply with putting current-breaker, new line and


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transformer.

The equipments that deteriorate power factor

Power Factor may be deteriorated by electrical equipments in the factory,especially by the inducible vibration-equipment in constant load.The general power factor per electrical equipment as follows;

Over 80% power factor: air conditioner(with qualified design), pump,grinder, air blower

Over 60-80% power factor: induction furnace, printer, textile machine Under 60 % power factor: compressor, auto-machine, electro motor,

welding machine, final grinder,If you have the above mentioned equipments in your factory, you can reduce

consumable current with Motor Saver system.

Who get benefit from Motor Saver system?

The customers who use inducible loaded equipment can reduce electric chargeimmediately after Motor Saver installation. The inducible loaded equipmentmeans that all electric equipment making electromagnetic field likes motors, airconditioner, electric tools, refrigerator, compressor and fluorescent lamp.It is very easy to install Motor Saver and even no need to maintain it.

Motor Saver is a new, innovative item that working for 24 hours to save electriccharge of customers and it has been achieved recognition for commercial andindustrial field, that is certified by test result. Moreover, Motor Saver has beencertified that it can reduce 10%-24% of electric charges by users.This fact means that investment would be retrieved within 2 years in the light of

Philippines electric charges system.

Motor Saver Systems Gain.

1. Improvement of Power FactorPower Factor is the ratio of active power[current] against total consumablepower[current]. In other words, the ratio of effective power to apparent power.

Power Factor is showed with (decimal) point under 1(one) or percentage.

Power Factor(PF) = Effective (Electric)Power / Apparent Power

= 60 KW / 100 KVA= 0.6 ( 60 % )

The best effect of Power Factor Improvement is to reduce the current passingthrough the distribution line and the following gain will immediately be acquired.

A. Consumable Apparent Power for acquiring same effective power

; In case the electric charges largely affect the capacity of accommodated


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current, profit would be big.

Ex.) KVA necessary in actual power 600 KWPower Factor 60% 70% 80% 90% 100%

Effective power 600 KW 600 KW 600 KW 600 KW 600 KWWattless power 800 KVAR 612 KVAR 450 KVAR 291 KVAR 0 KVAR

Total Power 1000 KVA 857 KVA 750 KVA 667 KVA 600 KVA

B. The Change of Effective Power Volume in same Apparent PowerIn case Motor Saver is installed, it can reduce consumable power of

transformer and distribution line in the factory. From the result, it is availablefor additional installation of motor, lighting fixtures or heater in the factory. Andit can mitigate the load of electric equipments that have excessively beenoperated and lengthen its life span and keep far stable voltage.

In example (1),it shows how the process is going on.Before the installation of Motor Saver, this motor needed 10 ampere but only

8 ampere needed after installation of Motor Saver, that means 20 % reduction.Thats because Motor Saver can supply magnetic current that necessary forthe motor. The ratio of reduction is depends on the type of motor.

Ex1) Picture

Ex)2 When 600 KVA is supplying ,the available volume of the effective power

Power Factor 60% 70% 80% 90% 100%Effective power 360 KW 420 KW 480 KW 540 KW 600 KWWattless power 480 KVAR 428 KVAR 360 KVAR 262 KVAR 0 KVAR

Total Power 600 KVA 600 KVA 600 KVA 600 KVA 600 KVA

C. Voltage-Improvement by improving voltage drop in lineIf the rated voltage is not available in a motor, it would be overloaded or

inappropriately operated. The graph shows change of the number of rotationand moving-torque depend on the impressed voltage.


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D. Smallization transformer and circuit breaker leads to reduce electric wireprice: In case of new facility

(Ex.)The following pictures indicate the required thickness of electric wire isdifferent depends upon power factor when 100 KW power supplied.

E. Line-Loss[I 2 R]Reduction =Proportional to the square of the current passingthrough.

The loss of electricity on the line =(square of the current passing through) x(line resistance) = I 2 RIf current is reduced 20% with Motor Saver, the loss of electricity on the line

would be reduced 36%.


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The ratio of line-loss[I 2 R] Reduction(%) =100 100 (previous Power Factor / new Power Factor)2

(Ex) In case Power Factor has improved from 65% to 90% ;

The ratio of Line-Loss[I 2 R] Reduction(%) = 100 100 (65 / 90)2

=48 %

2. Voltage Improvement, Illumination Efficiency Upgrade,& Efficiency ofmotor ImprovingThe low voltage is refined as words of high cost. Sometimes, excessive

voltages make lightening system as inefficient but proper motor managing notavailable in low voltage condition. Moreover, a lot of electric elements areworking under unfavorable conditions, and electric furnace cant radiate heat.

These kinds of problem are resulted from inducible load that necessary forwattless power and Motor Saver focuses to solve these problems.Motor Saver can improve voltage drop with supplying wattles power without

extra consumption of power. After all, Motor Saver can reduce electric chargeswith reduction of power consumption but also reduce maintenance expense andextend the life span of electric equipment.

(ex) In the ideal electric circuit, the phase of voltage and current arecoincided. This means 100% effective power is consumed in load condition.

In general electric equipments, the phase of voltage and current Are notcoincided due to inducible resistance and total efficiency on the line would be low.


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If some electric power system has difference in the phase as foregoing, eachelectric equipment needs more current-inflow to carry out the burden work. Thisleads also additional burden of line loss[I 2 R],consumable power volume, andmaintenance expenses. Just in that case, if you use Motor Saver, it wouldupgrade total efficiency of electric equipment depends upon the character ofindividual system and finally can reduce overall expenses including electriccharges.


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2 . Truth of Line loss (I2R) and Calculation Method

This report is written to deeply understand about line loss that occurs on the

electric wire. Generally, line loss is regarded as a not critical thing or inevitablehappening, but it affects seriously to the electric equipment and gives big burdenthing beyond the expectation. Therefore, we need to have systematic andscientific knowledge.

Outline of Line loss (I2R)

The expense of electric energy has continuously been increased and shall bemore critical. Therefore, we need to be keenly care in electric using. The usage

of electric power is divided into two, that is, the actual work and the wastefulpower. The power used for actual work is desirable and shouldnt be reduced forany reason, on the other hand, we should minimize the wasteful wattles power.

The electricity is supplied to the end users through transmission line from thepower plant and each end from end user the electric power is inflow into end-load through distribution line. On the electric transmission and distribution lines,line loss occurs when power is supplied, it is called as Line loss(I2R) and Iexplain about it. is the current pass through the each wire, is resistance on the wire,

and then line loss is (I2R).This Line loss is given off in the air as heat. R-

resistance on wire is a little bit changed by outside temperature but I ignore thatin this report.To reduce Line loss, we have to enlarge size of conductor[cross section] or

reduce passing current. In order to enlarge the size of conductor, we should usethick wire and its price will be increased considerably. Therefore, you are stronglysuggested to use Motor Saver to reduce passing current and it would be veryeffective choice.In electric load, there are two kinds, that is, resistant-load and inducible- load.

Since the resistant-load is 100% effective power and no more save whileinducible-load is mixed with effective and wattles power and total consumed

power beyond the effective power volume. Of that, the wattless power isconsumed for supplying of magnetic current of inducible-load and has nothing todo with actual work. Therefore, current on line requires additional wattles powercompared to the resistance current.

If you supply Wattless power to inducible circuit by Motor Saver, wattless power-inflow would be cut from the electric company, at the same time, current passingthrough is reduced.

Now, Id like to remind of some point as follows;

According to Kirchhoffs law about series-parallel circuit, all voltage to the


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parallel load is same but the current is same as total of current passing througheach load. If put the branch circuit as dotted line in the following pictures, thetotal loaded-current is to be not 6A but 8A.

Therefore, total current in electric system means total current passing throughall branch circuits. Regardless the size ,if any load is added, the current from thatis increased and since it passes through same wire, Line loss is increased. Afterall, it is no choice but to reduce the current in order to Line loss.


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< Calculation method of Line loss and the effect as increased-load >

3 PHASE,240 VOLT,12,000 WATTS(power factor ; 100 % )


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We can the important fact as follows from the calculation example;(1) Even in the line that 100% power factor, line resistance occurs

inevitably.(Thats because even any conductor, resistance is existed. The onlysolution to reduce this is using expensive low-coefficient resistance likes goldor silver or copper its thicker conductor of large volume)

(2) Line loss occurred because of initial load of 12,000 Watts is 165 Watts. Bythe way, In case of increased 4 loads, Line loss will be increased 2819.29Watts. That is, the fact is not simple 165 Watts X 4 = 660 Watts. This meansthat Line loss is represented the square of line- current and each loaded-current affects accumulatively to the increase of Line loss.The below graph indicates the change volume of Line loss whenever current

is variable 5 Amps .You can get the fact that though current variable limit of 5 Amps, the total current is larger, variable range of Line loss is larger, thetotal current is smaller, variable range of Line loss is smaller,


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You can know Line loss reduction volume of motor that connected to somecircuit is same when power factor is compensated regardless of loaded orunloaded condition, from actual experiment in the laboratory or through math-

calculation.That is, in case unloaded 5HP motor that its initial power factor of 0.33 is

compensated to 0.6 with Motor Saver, its Line loss reduction volume would be 47Watts. This motor is even under loaded condition, its initial power factor o.7 iscompensated to o.9,its Line loss reduction volume would be 47 Watts also. Thatis, in case of 5 HP,3Phase motor, its power reduction is to be 47 Watts regardlessof loaded or unloaded condition. In the light of thus result, lets suppose that 5motors same as that in page 12 &13 connected from MCC part to voltmeterthrough sub-distribution part and main-distribution part.The concerned wire was properly designed and selected as indicated in the

pictures. Since the total currents consumed for motor operation have to passthrough each section wire from voltmeter, line loss(I2R),It has been calculated bythe section unit. (picture A.B,C,D,)In case Motor Saver that its capacity of 10 KVAR(or 2KVAR,5 sets)is attached to

these motors, Line loss reduced in section D is 235 Watts,507Watts in section C,321 Watts in section B, 207 Watts in section A. Accordingly, total line lossreduction volume is 1270 Watts.And you can have surplus capacity room to install additionally motor one set

without any protection apparatus or alternating to thicker wire as 14 A currentwould be reduced.


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In other words, you can get the overall Line loss reduction effect, not only insection D, but also in section A,B,C with reduced current 14 A after installationof Motor Saver. Moreover, this example is only one case limited to one field.Therefore, when you once install[attach] Motor Saver properly to each field, youcan achieve remarkable line loss reduction effect through overall electric system.Regardless of electric charge system is KWD or KWH, or complex chargessystem, you can get considerable cost reduction effect whenever & wherever.Especially, you can more gain from overall electric system when install [attach]

Motor Saver to near the end-load part.


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The load condition of 5 HP Motor / Vector

KVA = 5.27 KVA = total power

KVAR=3.73 KVAR= wattless powerKW = 3.73 KW = effective power

Power Factor: 70%Total current: 21.95 AMPSEffective current: 15.54 AMPSWattless current: 15.54 AMPS

The connected line to motor is # 310-16, 10 of copper wire of NEC.TABLE andover level. The resistance on this wire is 1.06 OHM per 1000 If the length of

motor and panel is 236, the resistance per one phase circuit is 0.25 OHM.

CONSUMABLE POWER : WORK 3730 KWI2R Line Loss 120 KW

TOTAL 3,850 KW

Attach 2KVAR-Motor Saver to the above circuit

KVA = 4.11 Total Power =17.13 AMPSKW = 3.73 Effective Power = 15.54 AMPSKVAR = 1.73 Wattless Power = 7.21 AMPS

Power Factor = .91

Total Power = Work 3,730 KWI2R Line Loss .073 KW

Total 3.803 KW


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Line Loss Calculated as below ;(X2-Y2)RX = AMPS(Before compensation of power factor)

Y = AMPS(After compensation of power factor)R = OHMS

Total Power before compensation = 3.850 KWTotal Power after compensation = 3.803 KW

.047 KW

Power Factor : .33 Power Factor : .6Phase Angle : 70.7 Phase Angle : 52.8 Unloaded Unloaded Before compensation (to P.F) After compensation (to

P.F)


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Power Factor : .7 Power Factor : .9Phase Angle : 45.6 Phase Angle : 25.84

Loaded Loaded Before compensation (to P.F) After compensation (to P.F)


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Conclusion

As stated in the foregoing papers Line Loss occurred when additionally attach aload to the existed wire is considerably larger than in case of making the individualload as sole wire.

Ex.)1 : See 20A passing on the circuit of 0.5 OHMS

In the case of that, Line loss is

Supposed this load is an inducible load that of 10 AMPS reactance, install Motor Saver onthe circuit and supply the loss of 10 AMPS, you can reduce total input-current as 10 AMPS.

From the calculation of Line loss after install Motor Saver, you can get

.Therefore, you can acquire electric gain of 150 Watts after install Motor Saver.

Ex.)2 Add a load to the circuit same in example 1.

Line Loss = 402 X 0.5 OHMS = 800 Watts

Install the same Motor Saver that reduced 10 A in example 1 to the circuit .In this case, thereduced currency is 13.56 A.


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Line Loss =(26.46) 2 X .5 OHMS = 350 Watts

That is, line loss deduction is 450 Watts.As explained before, in 2nd example, though the load has been increased two

times than 1st example, loss reduction volume has been 3 times.This is can be doneby only Motor Saver with its remarkable feature and quality.


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3. Difference of Motor Saver and Capacitor Bank

Commonly, condenser is installed in large sized building or receiving end impedanceof factory as following purposes;

1) Prevent from Power Factor Declining(prevent the loss by low power factor)

2) Enlarge suppliers power supplying ability.

One the other hand, Motor Saver is installed beside motor or inside panel to thefollowing purposes;

a)Prevent from Power Factor Decliningb)Enlarge suppliers power supplying ability.c)Enlarge the affordable ability of each panel and lined)Keep stable voltage by reduction of line loss.e)Reduction of line loss, maximum power demand, and consumable power

Of the above mentioned purposes, e) is main purpose of Motor Saver and of costdown.

In case condenser is connected in parallel on line, power factor is increased while

current passing through the line would be reduced. Therefore, the beneficiary fromthe condenser attaching is just the supplier of the electricity, the electric company.With tightly reducing the consumers consuming electric power, the company candrastically reduce not only the capacity of circuit breaker, automatic switch, andgenerator but also line loss but most customers still have problem of line loss andvoltage decline.But Motor Saver is different from this, as it is installed nearest in loaded parts, from

the installation point to the receiving end impedance, users are to be beneficiarywith diversified effects and finally, electric suppliers could become beneficiary also.In some cases, invest to Motor Saver would be burden than several condenser, it is

worthy enough to choose in the light of energy saving and upgrade function.


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4. Experimental Verification of Motor Saver Effect

In Motor Saver working place, it is very hard to compute KHW reduction volume byindividual load(end-line unit) except some special cases.

Even it is available to show KHW reduction status with spot experimental example,but it not easy to indicate the result example of considerable and accumulative effectwith using of Motor Saver for all facilities.

That is because as below;

First, reduced power by Motor Saver is total reduced volume of total line loss fromend-load Motor Saver attached to main meter on the line. Therefore, you should set

meter beside main meter since exact reduction volume is accumulative calculated inmain meter. However, the individual reduction effect by each Motor Saver isphysically impossible.

Second, if section circuit is exist, line loss is composed. That is, the total sectionloss is larger than grand total loss volume. This is PIGGY BACK phenomenon. Likethis, More Motor Saver installed in all load parts, more its reduction effective.

To conclude, even you can guess reduction volume by each motor, you cant

check all reduction volume through the main meter. Thats because there isntsection circuit between experimental meter and motor and reduction volume fromPIGGY BACK Effect is not clear.


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5. Proper Installation Way of Motor Saver

Motor Saver is a FAIL-SAFE CAPACITOR that approved by CSA and UL. All MotorSavers equipped with pressure cut-off apparatus and it would be separate and cut-off Motor Saver from outside circuit in case of accident.

As Motor Saver is connected in parallel to power transmission line of motor, it isnot obstructed for operation even during separated after accident. Concerned PowerFactor of inducible motor, it is recommended to observe the following installationstandard ;

1. When use the capacitor that power factor adjustable, you set total KVAR of

motor controller is under 1(one),,power factor during unloaded. If total KVARover 1(one),passing current is excessive and it leads to occur excessivevoltage, current, and torque.Therefore, it may lead physical risk or motor damage, or give ill affect todriving system.

2. In the following cases, you cant directly connect the capacitor that powerfactor adjustable to motor terminal. i.e.; elevator motor, multi-single speedfloating motor, plugging-jogging motor, star-delta motor, automatic transformer,driving motor, some motor for winding machine

3. If possible, itd better to install Motor Saver to . If so, it can keep the inflow-current to the relay that prevent overload motor, and then, no need to adjust the

relay. In case of ,you have to change the fix-current of the protect-relay. The

motor in the aforesaid article # 2 should be installed to . In any case, please dont

make excessive condition and set the power factor of BUS is not beyond 95%.

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