Question, 3ph line filter

Picked up a couple 15 amp 3ph line filters yesterday at a surplus
outlet. Units are mfg. by SAE Power, looked at their web site last night
and the units they show for 3ph have a neutral and ground connection
in addition to the three powered lines. This unit has only the power
connections. It's marked with what looks like a Varian P/N, and doesn't
look like the off-the-shelf units SAE lists on the web site. Probably a
custom unit. Would like to know if I will run into any trouble if my
ground wire isn't filtered.

Jon A