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  <xsd:element id="powl_DeferredCompensationPlanAssetsFairValueDisclosure" name="DeferredCompensationPlanAssetsFairValueDisclosure" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="powl_DocumentAndEntityInformationAbstract" name="DocumentAndEntityInformationAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="powl_EstimatedEarnings" name="EstimatedEarnings" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="powl_FacilityAgreementMember" name="FacilityAgreementMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="powl_GeneralElectricCompanyMember" name="GeneralElectricCompanyMember" 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_IncreaseDecreaseInAccountsPayableAndIncomeTaxesPayable" name="IncreaseDecreaseInAccountsPayableAndIncomeTaxesPayable" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" 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_LossContingencyProbableLossInPeriod" name="LossContingencyProbableLossInPeriod" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" 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 abstract="true" id="powl_PurchasedTechnologyMember" name="PurchasedTechnologyMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="powl_ShareBasedCompensationArrangementByShareBasedPaymentAwardPercentOfActualAmountOfUnitsEarned" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardPercentOfActualAmountOfUnitsEarned" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="powl_ShareBasedCompensationArrangementByShareBasedPaymentAwardTargetRSUGrantedRange" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardTargetRSUGrantedRange" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="powl_SupplyAgreementMember" name="SupplyAgreementMember" 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:schema>
