Motor power is one of the core parameters to ensure compressor to manage air discharge. The wattage rating is usually stamped on the motor's metal nameplate. { '.' var hour = document.getElementById('hour').value; } Brake horse power, BHP = GHP/ηM (kW) (1) Calculate from power into other power unit measures. The Power to Perform. First, he needs to convert everything to watts so he refers to the above Power … if(hour == "") else document.getElementById('hour').focus(); For the 200 cfm load: Specific power of the VSD at 41% load (200/488) from Figure 5 = 20.2 kW/100 cfm. HP = horsepower. } CheCalc Chemical engineering calculations to assist process, plant operation and maintenance engineers. var rgx = /(\d+)(\d{3})/; { P actual_centrifugal = P poly / Ep = 165.7*0.702 = 236 kW. The goal of compressor sizing calculations is often to find out the efficiency of the compressor and power required to drive that compressor, given the gas composition, flow rate, temperature & pressure conditions at inlet and outlet pressure requirement. else A plant once found that its two 150-hp rotary-screw compressors couldn’t maintain the required minimum pressure (Figure 1). document.getElementById('net_profit').value = round_up(document.getElementById('energy_cost').value / 0.08); Find Your Compressor. He needs to run an air compressor and a pressure washer. { var ME = document.getElementById('me_val').value; return false; View Newsletter Archives », © 2009-2021 Lewis Systems and Service Company. Specific power is like a gas mileage rating for compressors and shows the ratio of the total package power input kW of a complete compressor package, including cooling fans, pumps, and other electrical loads for every 100 cfm of output, not just the break horsepower on the screw inlet shaft. { AC single phase amps to kilowatts calculation. if (!RE_NUM.test(cost)) { As a unit of conversion, there are 0.746 KW in 1 hp. return x1 + x2; N = number of compression stages. x1 = x1.replace(rgx, '$1' + ',' + '$2'); document.getElementById('net_profit').value = addCommas(document.getElementById('net_profit').value); As a unit of conversion, there are 0.746 KW in 1 hp. Table 3 shows the inlet volumetric flow rates required to achieve 350 ton of cooling. document.getElementById('bhp').focus(); { if (!RE_NUM.test(bhp)) { document.getElementById('calculation_result').style.display = 'block'; CheCalc Chemical engineering calculations to assist process, plant operation and maintenance engineers. The higher the capacity the more power is consumed. document.getElementById('energy_user').value = round_up(((bhp * 0.746) / ME ) * hour); Reciprocating Compressor Calculation estimates Temperature Rise and Power Consumed in compressing a gas mixture from an Inlet Pressure to Desired Outlet pressure. } Convert 10 hp to kW: P (kW) = 0.746 ⋅ 10hp = 7.460 kW . x2 = x.length > 1 ? The air compressor is 3.8kW startup and 1.1kW running. function cal_kWh() return false; So, we can determine the energy cost to spin the electric motors. The goal of compressor sizing calculations is often to find out the efficiency of the compressor and power required to drive that compressor, given the gas composition, flow rate, temperature & pressure conditions at inlet and outlet pressure requirement. To Save a Buck. Power P, kW {P1*100000*Q1*ln (P2/P1)}/1000 ISOTHERMAL COMPRESSION IS FOR ACADEMIC PURPOSE ONLY. x = nStr.split('. The power P in kilowatts (kW) is equal to the power factor PF times the phase current I in amps (A), times the RMS voltage V in volts (V) divided by 1000: P (kW) = PF × I (A) × V (V) / 1000. document.getElementById('energy_cost').value = addCommas(document.getElementById('energy_cost').value); Combined brake horsepower rating of operating air compressors, ME: 0.96 0.95 0.94 0.93 0.92 0.91 0.90 0.85, www.epa.gov/cleanenergy/energy-resources/refs.html, Sullair Introduces Oil Free Portable Air Compressor, BEKO Appoints Yannick Koch as Managing Director, Victaulic Appoints Dr. Richard A. Bucher as Chief Executive Officer. Please use the calculator below to achieve an understanding of the kWh consumed (or saved) in your compressed air system. With : P is =Power (kW) Z = gas compressibility factor (can be defined on an Amagat diagram by calculating the reduced pressure and reduced temperature of the gas) P 1 = Pressure inlet compressor (kPa) P 2 = Pressure outlet compressor (kPa) Q m =Compressor throughput (kg/s) … (You can read more about air compressors HERE). In instances when only the amperage rating is given, determine watts used by multiplying the voltage by the number of amps. nStr += ''; Simple Energy Formula: Motor Efficiency = Cost per KW X .746 (Power Factor) X Hours of operation X Brake horsepower *Note: No electric motor is 100% efficient, most will average 92-95% efficient. Motor power is one of the core parameters to ensure compressor to manage air discharge. 2.5 STEP 5 : calculate the actual power required. PSI VS. alert('Please enter some value for cost'); Weight flow-lb/min, lb/h (kg/min. Design Studies. alert('Please enter some value for bhp'); document.getElementById('energy_cost').value = round_up(document.getElementById('energy_user').value * cost); II. else alert('Please enter some value for cost'); } This works out to … else Web design by, Kobelco KNW Series Oil-Free Rotary Screw Air Compressors, Powerex Industrial, Medical Air & Gas Products. Specific power is like a gas mileage rating for compressors and shows the ratio of the total package power input kW of a complete compressor package, including cooling fans, pumps, and other electrical loads for every 100 cfm of output, not just the break horsepower on the screw inlet shaft. var ME = document.getElementById('me_val').value; } function addCommas(nStr) { while (rgx.test(x1)) { return false; { document.getElementById('energy_cost').value = addCommas(document.getElementById('energy_cost').value); if(bhp == "") if (!RE_NUM.test(cost)) { To account for non idealities, the calculation will have to be corrected by an efficiency coefficient (η)dependent on the technology used and which should be precised by the manufacturer. The power required for adiabatic (process without transfer of heat) compression of air can be expressed as. } First, he needs to convert everything to watts so he refers to the above Power Reference Table; if(cost == "") } else { var cost = document.getElementById('cost').value; document.getElementById('energy_user').value = addCommas(document.getElementById('energy_user').value); As can be seen HFO1234ze(E) requires a 33% (.601/.450) larger volumetric flow rate. } var hour = document.getElementById('hour').value; document.getElementById('metric_ton').value = round_up(document.getElementById('energy_user').value * 0.000718); For 1 compressor stage, the isentropic compressionis the following : Pis = 2.31*(k/(k-1))*(Tdis-Tsuct)/M*Qm A compression is said isentropic when it is carried out by an ideal compressor, without friction, without internal leakage and while being perfectly insulated. document.getElementById('net_profit').value = addCommas(document.getElementById('net_profit').value); Pl do needful how to calculate in reduction of Pressure in Reciprocation air compressor. 14.7 psia and dry 3. number of mols/h None of these flows can be used directly in calculating compressor performance. } Specific power at 30% load would be 21.8 kW/100 cfm from Figure 5. kWh = (cfm x specific power x hours)/100 = (148 x 21.8 x 3000)/100 = 96,790 kWh. So, we can determine the energy cost to spin the electric motors. x1 = x1.replace(rgx, '$1' + ',' + '$2'); "); All must be converted to ACFM-actual cubic feet per minute. document.getElementById('energy_user').value = addCommas(document.getElementById('energy_user').value); '.' return Math.round(val); else { { This calculator will help you determine your power requirements, as well as how many compression stages you will need for your process conditions. You can access a free Excel calculation tool to make the compressor power calculation explained above : Compressor Power Calculator This adds to the total. if(hour == "") document.getElementById('energy_cost').value = round_up(document.getElementById('energy_user').value * cost); document.getElementById('energy_user').value = round_up(((bhp * 0.746) / ME ) * hour); The kW output of your compressor motor is divided by the electrical efficiency to give the electrical input power that your compressor uses. // -->. Diferent power units conversion from kilowatt to atmosphere cubic feet / minute. Lastly, the pressure washer manual indicates it needs 15.0 Amps max and 5.4 Amps continuous. L=0.04 for lubricated compressors (only for estimation) c must be defined according to the compressor type but should range from 0.04 to 0.16. It has electric powered cooling fans that consume extra power over and above the nominal rating. return false; return false; function cal_kWh() alert("Please enter numeric values only. alert('Please enter some value for bhp'); Main components of centrifugal compressor are Casing, Shaft, Impellers, Bearings, Diaphragms and Seals. { Air Conditioning - Air Conditioning systems - heating, cooling and dehumidification of indoor air for thermal comfort; Related Documents . The finder will select the best match from our line of standard compressors, but we can also design a custom solution to meet any requirement. return false; P (kW) = I (A) × V (V) / 1000. Failure to calculate the power correctly may result in power consumption without effect. '); if (!RE_NUM.test(hour)) { document.getElementById('metric_ton').value = addCommas(document.getElementById('metric_ton').value); return false; Watch our latest video to learn what can happen when you choose an air compressor provider that offers low-quality products and services. if(cost == "") ");