Yes, you can use the PC-501A for bilayer measurements.

However, you will need to reconfigure your amp to use the 5101-10GB bilayer headstage since a regular patch-clamp headstage cannot pass the current required to charge the membrane capacitance.

One other thing to note, determining bilayer capacitance using a patch-clamp amplifier and patch-clamp software (e.g., pClamp) will not give you correct values for membrane capacitance. This is because the capacitance measurement algorithm within the software is designed expressly  for whole cell capacitance measurements.

In this case, Molecular Devices (manufacturer of pClamp) suggests that you follow a protocol to measure capacitance rather than rely on the algorithm within pClamp. The same protocol is indicated for Warner patch clamp amps under similar conditions.

If these issues are a burden, note that the Warner Bilayer Clamp amp has the appropriate capacitance measurements capability, as well as several other needed tools, already built into it.