will have the added benefit of significant time saving importantly it should be noted that the downhole switch 26 can be located anywhere under the wellhead 10 but the lower it is positioned in the well the less cable 14 is deployed downhole which means lower cabling costs in fact the choice to position the switch 26 directly under the wellhead 10 or at the upper dual esp 24 u will differ from case to case cable 14 is more vulnerable the deeper it goes so some users may wish to double the cable 14 on the underside of the wellhead 10 to maximize the reliability of the system and to avoid the potential failure on the cable 14 leading to both esp units 24 u 24 l being inoperable typically if a packer 22 is used the cable 14 below the packer 22 is more vulnerable to downhole conditions than the cable 14 above the packer accordingly the choice of positioning the switch 26 above or below the packer 22 will be made on a case by case basis depending on the operator 39 s requirements if desired the switch 26 could be modified by those skilled in the art without departing from the scope of the invention to provide third and fourth positions to allow further esps 24 to be added if for instance a triple or quadruple esp 24 system was required by an operator 1 only one power cable 14 to surface is required and thus the cable 14 cost is potentially halved 2 only require a single penetrator at packer 22 and thus a standard esp packer 22 can be used 3 only require a single penetrator 12 at wellhead 10 and thus a standard esp wellhead 10.