Penetrator OVA network Promiscuous mode

Do I need to set Promiscuous mode?

I wish only use penetrator for web site assessment.

What is the scope of setting Promiscuous mode on the network card?

Promiscuous mode should is not needed on the Penetrator. You can simply run and deploy it.
However, if you are also testing the Protector UTM Firewall, it may need to run in bridge mode.