Try this
<system.serviceModel>
<bindings>
<basicHttpBinding>
<binding name="OMCServiceSoap" maxReceivedMessageSize="10000000">
<readerQuotas maxDepth="2147483647" maxStringContentLength="2147483647" maxArrayLength="2147483647" maxBytesPerRead="2147483647"/>
</binding>
</basicHttpBinding>
</bindings>
<client>
<endpoint address="http://localhost/1820/Service/OMCService.asmx"
binding="basicHttpBinding" bindingConfiguration="OMCServiceSoap"
contract="ServiceReference.OMCServiceSoap" name="OMCServiceSoap" />
</client>
</system.serviceModel>