guarded capacitor excitation in hfss

hello! I am new to HFSS and am not sure how to excite my capacitor structure. It is a cylindrical capacitor (plates along the curved edges of the cylinder). I am stumbling on how to excite it, as I have 3 electrodes. I'd like to be able to have the high electrode at +V/2, low at -V/2 and the guard electrode at 0 or +V/2. Is this possible?