How to limit Network VM by powercli

Hello,

     I would like to change many Virtual Machine Network Limit via Powercli/powershell. It's very easy in virtual console but not in powershell

i know how to see the limit by this command

     $vm=get-vm -vm "AZERTY"

     ($vm|get-networkadapter).ExtensionData.ResourceAllocation.limit

          or

     $vm.NetworkAdapters[0].ExtensionData.ResourceAllocation.Limit

but it's not possible to change limit by this method and the option doesn't exist with set-networkadapter or by use VMware.Vim.VirtualMachineConfigSPec

Can you help me please :-)))

Thank You

Yannick Lecaille