So in summary, when each single phase 208V load is drawing 34.64A, the 3-phase … Motor volts are 380 volts, Eff is 0.89 and PF is 0.85 according to the above nameplate. This chart approximates the amperage of a generator based on the size of the generator and the load on the generator at 100 percent of capacity. Enter the kilovolts-amps followed by the volts in the same order. So our motor power is 15KW with 15 x 1000 = 15000 Watts. The power taken by a circuit (single or three phase) is measured in watts W (or kW). Power factor (cosΦ). I should of checked the voltage. Three phase AC The three-phase ac amps involve HP * 746 in the numerator and 1.73 times PF * Efficiency times voltages in the denominator. The diagram and table below can be used to convert amperage between single phase and three phase equipment and vice versa. Calculate Required UPS Size Phase Required 1 3 Volts Required. AC three phase watts to amps calculation Calculation with line to line voltage. The three-phase ac amps involve HP * 746 in the numerator and 1.73 times PF * Efficiency times voltages in the denominator. For example, if A = 5.1A, B = 5.0A, C = 5.2A, you would say, "The current is 5.1A" That phrase means the currents are reasonably balanced and 5.1A is an average number. Out of these cookies, the cookies that are categorized as necessary are stored on your browser as they are essential for the working of basic functionalities of the website. Electrical calculators is collection of tools, reference tables, formulas and electrical reference tables which helps you boost your productivity. Amps to Watts Calculator. Electrical calculators provides powerful automation tools to boost your productivity. The three phase power calculator calculates the active and reactive power current from the following parameters: Voltage (V): Enter the phase-to-phase (\(V_{LL}\)) voltage for a 3-phase AC supply in volts. These cookies will be stored in your browser only with your consent. Example: Determine the current flowing through a two-phase, 0.5 HP, 220 volt motor having an efficiency rating of 90% and a power factor of 0.92. The formula is identical to the previous case with the difference of factor 1.73 instead of 2 in the denominator. You also have the option to opt-out of these cookies. If we had a single phase system, that 3000 watts would be drawing 30 amps, as 30 amps times 100vrms is 3000 watts (resistive). It has two types, single phase and three phase transformer. The two phase calculations are similar to 1 phase with an additional factor 2 in the denominators. Ohm's Law Calculator 3-Phase Delta / Wye Calculator. Transformer Amps from kVA rating Formulas, Examples for Transformer Amps calculations, 500 kVA Transformer Chart for Different Voltage Levels, 1000 kVA Transformer Chart for Different Voltage Levels. Single & Three Phase Line kVA calculator is an online tool used in electrical engineering to measure the unknown quantity by two known quantities applied to the below formulas for single phase and three phase connection. My calculation was 11500/(1.732x400) = 16.6 Amps per phase ... 16.6 x 3 = 49.8 Amps, so i need a 50 Amp breaker. Amps per leg on three phase?? I will do that tomorrow. These cookies do not store any personal information. What is causing the .6 reading on one leg? After the steps above the final formula for converting horsepower to amps is: Amps = HP × 746 V × η × PF. A 3 phase transformer has three magnetic circuits that are interlaced to give a uniform distribution of the dielectric flux between the high and low volts windings. Solution: Current = [2 * 746] / [400 * 0.93 * 0.9 * 1.732] = 2.57 Amps. From your question it seems this is a theoretical question. Given the kW and power factor the kVA can be easily worked out. Leverage Watlow's growing toolkit of calculators, equations, reference data and more to help design your thermal system. This website uses cookies to improve your experience. Any cookies that may not be particularly necessary for the website to function and is used specifically to collect user personal data via analytics, ads, other embedded contents are termed as non-necessary cookies. Ampere (amps or amperage) is an SI unit of electric current and is denoted by 'A'. The formula is identical to the previous case with the difference of factor 1.73 instead of 2 in the denominator. HP to Amps calculator is used to calculate the amperes from horsepower of the motor is known. User manuals, specification sheets, CAD drawings and more. For three phase circuits the power factor is the square root of 3. We'll assume you're ok with this, but you can opt-out if you wish. 3 phase motor current calculation formula is P/ (√3xVxPfxEff) or P/ (1.732xVxPfxEff) Both are the same. Three phase Amps =  [HP * 746] / [E * %age Efficiency * PF * 1.73]. It is mandatory to procure user consent prior to running these cookies on your website. I got 9-.6-9 It sounds good. A 60A 3-phase branch circuit has 60A available on each leg. If your calculator doesn’t have a square root function, use 1.73 as an approximation of the square root of 3. User manuals, specification sheets, CAD drawings and more. I got 9-.6-9 It sounds good. Solution: Current = [0.5 * 746] / [220 * 0.88 * 0.9 * 2] = 1.07 Amps. The total power is 3000 watts. Use this online transformer capacity calculator to find its volts, kVA and amps For three phase motor amps calculation, the below formula is used. This website uses cookies to improve your experience. Rang the electricity supplier and they said you can request for whatever (not quite her words) as long as you can provide justification for it. Any cookies that may not be particularly necessary for the website to function and is used specifically to collect user personal data via analytics, ads, other embedded contents are termed as non-necessary cookies. Starting & Running current are the three important factors for the rating of AC induction motor. They also don't charge any extra for going up in amps (which seems strange to me but that's what she said). Single phase Amps = [HP * 746] / [E * %age Efficiency * PF]. It has two types, single phase and three phase transformer. But opting out of some of these cookies may have an effect on your browsing experience. quantity 1 3 phase 80 amp breaker quantity 8 3 phase 60 amp breaker quantity 6 3 phase 30 amp breaker all these loads are continuous duty as they run machines that never shut down and if i calculate for worse case scenario i would add all the breakers and multiply by .80 coming up with 592 amps. Necessary cookies are absolutely essential for the website to function properly. Electrical calculators provides powerful automation tools to boost your productivity. Amps = Watts ÷ Volts. The product of the voltage and current is the apparent power and measured in VA (or kVA) . The three-phase power calculator calculates the apparent, active and reactive power for three-phase AC systems. Jraef. If a three-phase supply is available, then the 24,000 watts are divided by … We also use third-party cookies that help us analyze and understand how you use this website. This category only includes cookies that ensures basic functionalities and security features of the website. These cookies do not store any personal information. This website uses cookies to improve your experience while you navigate through the website. We'll assume you're ok with this, but you can opt-out if you wish. Decided to check the amps on a three hp motor. In certain cases even more advanced options are … Transformer kVA to Amps Rating Calculator with Calculations and Examples [Single/Three Phase Transformer], Circuit Breaker Breaking Capacity Calculator, Digital Calculator [Binary – Octal – Decimal – Hexadecimal], 500 kVA Single Phase Transformer: I = 500 * 1000 / 3.3kV = 151.5 Amps, 500 kVA Three phase Transformer: I = 500 * 1000 / (3.3 * 1.73 kV) = 87.58 Amps, 1000 kVA Transformer Single Phase Amps when V = 33 kV: 30.30 A, 1000 kVA Transformer Single Phase Amps when V = 33 kV: 17.51 A. The resulting value is the amount of power, expressed in amps, required at the input side of phase converter. To calculate kVA, you need to enter the known values of voltage and the current into the respective fields. I will do that tomorrow. AC three phase kilowatts to amps calculation Calculation with line to line voltage The phase current I in amps (A) is equal to 1000 times the power P in kilowatts (kW), divided by square root of 3 times the power factor PF times the line to line RMS voltage VL-L in volts (V): I(A) = 1000 × P(kW) / … Two-phase Amps = [HP * 746] / [E * %age Efficiency * PF * 2]. 02-24-2017, 07:36 PM #2. Find the amperage rating of a transformer having 225 kVA and 500 V in case of single and three phase. Jraef. Example: Determine the current flowing through a three-phase, 2 HP, 400-volt motor having an efficiency rating of 93% and a power factor of 0.9. The single phase AC calculations involve the power factor in denomatior of equation. The transformer kVA rating can be used to calculate amps. Three-phase Transformer Amps = Transformer kVA rating * 1000 / (E*1.73) Examples for Transformer Amps calculations 225 kVA, 3.3 kV Transformer amps. The formula to convert kVA to amps in a three-phase circuit looks like this: Current (A) = Power (kVA) × 1,000 √3 × Voltage (V) So, amps are equal to 1,000 times the power in kVA divided by the square root of 3 (1.732) times the voltage. GENERATOR AMP RATINGS - THREE PHASE EXTENDED: 3 PHASE AMPERES - 80% POWER FACTOR* (Extended Table) kW Times 1000 divided by (Volts*1.73) *.80. It's … To get the current amps, you will begin by selecting the phase which can be either a single phase or a three phase. If we divide 30 by 3 we get 10, the current in each phase of the three phase system. As a "rules of thumb" amps horsepower rating can be estimated to. FORMULAS USED IN CALCULATOR: 1-Phase KVA = Volts x Amps / 1000 1-Phase Amps = KVA / Volts x 1000 3-Phase KVA = Volts x Amps x 1.732 / 1000 3-Phase Amps = KVA / Volts / 1.732 x 1000 What is causing the .6 reading on one leg? Example: Find the current passing through 24 volt, 1/2 HP motor having an efficiency of 95%. Do not say "Amps per phase", or "Amps per leg". Perform a three-phase power calculation using the formula: P = √3 × pf × I × V Where pf is the power factor, I is the current, V is the voltage and P is the power. From your question it seems this is a theoretical question. Solution: Current = [0.5 * 746] / [24 volt * 0.95] = 16.35 Amps. Amps per leg on three phase?? Neither of those terms have any meaning. 115 volts motor - single-phase : 14 amps/hp; 230 volts motor - single-phase : 7 amps/hp; 230 volts motor - 3-phase : 2.5 amps/hp; 460 volts motor - 3-phase : 1.25 amps/hp; Always check nameplate information before designing protective devices, wiring and switch gear. You can use the Electrical calculator to find the current in single, 2, and 3 phase motor circuits as well as in dc circuits. If your calculator doesn’t have a square root function, use 1.73 as an approximation of the square root of 3. Most AC power is produced and distributed as three-phase power with three sinusoidal voltages 120 degrees out of phase with each other.. Typically, two options are offered: permanent magnet or auxiliary winding. Calculation of AC Single phase Kilowatts to amps I (A) = 1000 x P (kW) / (PF x V (V)), which means that the phase current in amps is calculated by multiplying 1000 by the power in Kilowatts dividing the result by the power factor multiplied by the RMS voltage in volts. Single-phase Transformer Amps = Transformer kVA rating * 1000/E, Three-phase Transformer Amps = Transformer kVA rating * 1000 / (E*1.73), Find the amperage rating of a transformer having 225 kVA and 500 V in case of single and three phase, In the case of single-phase: I = 225 * 1000 / 3.3kV = 68.18 Amps, In case of three-phase: I = 225 * 1000 / (230 * 1.73) = 39.41 Amps. 3 phase "100 amps per phase" can someone explane "phases" to an idiot? DC Amps = [HP * 746] / [E * %age Efficiency]. Power Factor 0.8 0.9 0.95 Generator Power (kW) = Generator Power (kVA) 75% Continuous Load (kVA) Converting kW to HP kW = HP. Current (I): Enter the the current in Amperes (A). I have a 65 amp machine but trying to get a machine that can go up to 130 amps but I control the amperage besides it will be a while and I need a place to get it up and runing and dialed in. Then compute I per (conductor or leg) using the rule that on a three phase system current on an individual conductor is 1/ (3^0.5) = 1/1.73 of the total current. Necessary cookies are absolutely essential for the website to function properly. 02-24-2017, 07:36 PM #2. Out of these cookies, the cookies that are categorized as necessary are stored on your browser as they are essential for the working of basic functionalities of the website. 1 watt is defined as the energy consumption rate of one joule per second. The current is simply the kVA divided by the voltage. As per my understanding & without other variables, this is the simple solution I could think of. In a single-phase AC power system there is only one single sinusoidal voltage. Ohm's Law Calculator 3-Phase Delta / Wye Calculator. The rms current per phase is 100/10=10 amps. Example: Determine the amps in single phase 1 HP, 120-volt motor having an efficiency rating of 88% operating at a power factor 0.9. The resulting value is the amount of power, expressed in amps, required at the input side of phase converter. In the case of single-phase: I = 225 * 1000 / 3.3kV = 68.18 Amps. The power per phase is 1000 watts. The relationship between kVA and kW is the power factor (pf):Single phase system - this is the easiest to deal with. Decided to check the amps on a three hp motor. This video is about 3 phase motor amps calculation Or 3 phase motor current calculation guide. HP to Amps Conversion Calculator [3 Phase, Single, Two Phase, DC] | Horsepower to Amperes, Circuit Breaker Breaking Capacity Calculator, Digital Calculator [Binary – Octal – Decimal – Hexadecimal]. But opting out of some of these cookies may have an effect on your browsing experience. GENERATOR AMP RATINGS - THREE PHASE EXTENDED: 3 PHASE AMPERES - 80% POWER FACTOR* (Extended Table) kW Times 1000 divided by (Volts*1.73) *.80. I should of checked the voltage. Solution: Current = [1 * 746] / [120 * 0.88 * 0.9] = 7.84 Amps. The builder has said to request for 3 phase 40amps per phase. Amps per Phase. Watt is an SI unit of electric power and is denoted by 'W'. This website uses cookies to improve your experience while you navigate through the website. For three phase circuits the power factor is the square root of 3. FORMULAS USED IN CALCULATOR: 1-Phase KVA = Volts x Amps / 1000 1-Phase Amps = KVA / Volts x 1000 3-Phase KVA = Volts x Amps x 1.732 / 1000 3-Phase Amps = KVA / Volts / 1.732 x 1000 Thus, the current in amps is equal to horsepower times 746 divided by the voltage times the efficiency η times the power factor. Here’s a simple example of the equation: You’re preparing to drive a three phase low-horsepower motor rated at 10 amps. So you have 60A available on each leg for your loads. For example, a three phase circuit using 25,000 watts of power and a line voltage of 250 will have a current flow of 25,000/(250 x 1.73), which is equal to 57.80 amperes. These cookies will be stored in your browser only with your consent. (in each of the three wires) If it was a heating load, cos phi is 1 so the answer would be 8 amps. Enter the power factor of the load. As per my understanding & without other variables, this is the simple solution I could think of. A 3 phase transformer has three magnetic circuits that are interlaced to give a uniform distribution of the dielectric flux between the high and low volts windings. How to Convert kVA to Amps in Three-Phase Circuits. In DC circuits amps is the ratio between the product of HP * 746 to Voltage times efficiency. If you have say a 6kW load motor), that's 2kW per phase, divide by 240 equals about 8 amps, divide by your power factor (cos phi) [say 0.8] equals 10 amps. As an example, consider a loa… Both provide the generator with three times their nominal current to cover inrush peaks from the electrical motor, for a minimum duration of ten seconds, via a residuary excitation current. It is mandatory to procure user consent prior to running these cookies on your website. 1 Ampere is defined as the electrical current that flows with electric charge of one Coulomb per second. Electrical calculators is collection of tools, reference tables, formulas and electrical reference tables which helps you boost your productivity. The solution is to calculate the VA = E x I transposed to I = VA / E to get total amps. How to Convert kVA to Amps in Three-Phase Circuits. This category only includes cookies that ensures basic functionalities and security features of the website. The current in amps multiplied by voltage in volts gives power in watts (Power = voltage x current). Here’s a simple example of the equation: You’re preparing to drive a three phase low-horsepower motor rated at 10 amps. Hi, i'm a little confused about the way to calculate the amp of the circuit breaker for a three-phase system. Still I will try to attempt this. We also use third-party cookies that help us analyze and understand how you use this website. Back to the main topic: You also have the option to opt-out of these cookies. Use this online transformer capacity calculator to find its volts, kVA and amps Leverage Watlow's growing toolkit of calculators, equations, reference data and more to help design your thermal system. Starting Current, sometimes abbreviated as I start in electrical engineering, is a measure or rating of how much current required for a single or three phase AC motor to get started. Still I will try to attempt this. For a normal, single-phase power supply at 240 volts, the maximum current would be 100 amps. If the three phases are reasonably balanced - list that current. The formula to convert kVA to amps in a three-phase circuit looks like this: Current (A) = Power (kVA) × 1,000 √3 × Voltage (V) So, amps are equal to 1,000 times the power in kVA divided by the square root of 3 (1.732) times the voltage. This chart approximates the amperage of a generator based on the size of the generator and the load on the generator at 100 percent of capacity. Ideally I'd need 150 amps but 100 amps would be OK. It is a conversion calculator which converts Kilovolts-amps (kVA) with the voltage in volts to amps (A). If i have a power of 11.5 kW and voltage of 400V, what size circuit breaker is needed for three-phase system. Here is a breakdown of your situation of the delta connected single phase loads.