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  <xsd:element abstract="true" id="powl_FacilityAgreementMember" name="FacilityAgreementMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="powl_IncreaseDecreaseDueToForeignCurrencyTranslation" name="IncreaseDecreaseDueToForeignCurrencyTranslation" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="powl_IncreaseDecreaseInContractWithCustomerAssetAndLiabilityNet" name="IncreaseDecreaseInContractWithCustomerAssetAndLiabilityNet" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="powl_IndustrialDevelopmentRevenueBondsMember" name="IndustrialDevelopmentRevenueBondsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="powl_LineOfCreditFacilityCollateralAmount" name="LineOfCreditFacilityCollateralAmount" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element id="powl_LineOfCreditFacilityCovenantTermsCashCollateralPercentOfDebtOutstanding" name="LineOfCreditFacilityCovenantTermsCashCollateralPercentOfDebtOutstanding" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="powl_MexicoCentralAmericaAndSouthAmericaMember" name="MexicoCentralAmericaAndSouthAmericaMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="powl_NonEmployeeDirectorEquityIncentivePlanMember" name="NonEmployeeDirectorEquityIncentivePlanMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="powl_OtherCustomersMember" name="OtherCustomersMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="powl_PercentageOfDomesticCapitalStockPledgedAsCollateralForCreditFacility" name="PercentageOfDomesticCapitalStockPledgedAsCollateralForCreditFacility" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element id="powl_PercentageOfNonDomesticCapitalStockPledgedAsCollateralForCreditFacility" name="PercentageOfNonDomesticCapitalStockPledgedAsCollateralForCreditFacility" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="powl_PerformanceBasedRestrictedStockUnitMember" name="PerformanceBasedRestrictedStockUnitMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="powl_PowellUKLimitedMember" name="PowellUKLimitedMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="powl_RatioOfConsolidatedEarningsBeforeInterestTaxesDepreciationAndAmortizationLessIncomeTaxesCapitalExpendituresPrincipalDebtPaymentsAndInterestCharges" name="RatioOfConsolidatedEarningsBeforeInterestTaxesDepreciationAndAmortizationLessIncomeTaxesCapitalExpendituresPrincipalDebtPaymentsAndInterestCharges" nillable="true" substitutionGroup="xbrli:item" type="xbrli:pureItemType" xbrli:periodType="duration" />
  <xsd:element id="powl_RatioOfIndebtednessToConsolidatedEarningsBeforeInterestTaxesDepreciationAndAmortization" name="RatioOfIndebtednessToConsolidatedEarningsBeforeInterestTaxesDepreciationAndAmortization" nillable="true" substitutionGroup="xbrli:item" type="xbrli:pureItemType" xbrli:periodType="duration" />
  <xsd:element id="powl_RestrictedCashFairValueDisclosure" name="RestrictedCashFairValueDisclosure" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element id="powl_RevenueFromSalesOrdersPercentage" name="RevenueFromSalesOrdersPercentage" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="powl_RevenuePerformanceObligationSatisfiedOverTimePercentage" name="RevenuePerformanceObligationSatisfiedOverTimePercentage" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="powl_ShareBasedCompensationArrangementByShareBasedPaymentAwardAnnualSharesIssuable" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardAnnualSharesIssuable" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration" />
  <xsd:element id="powl_ShorttermInvestmentsFairValueDisclosure" name="ShorttermInvestmentsFairValueDisclosure" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="powl_TheThirdAmendmentMember" name="TheThirdAmendmentMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="powl_TimeBasedRestrictedStockUnitMember" name="TimeBasedRestrictedStockUnitMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="powl_TractionPowerCustomerMember" name="TractionPowerCustomerMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
</xsd:schema>
