I know when stacking variacs they use a paralleling choke. Not sure if this same technique would or could apply to HV plate transformers. Jeff -------------- next part -------------- Outgoing mail is certified Virus Free. Checked by AVG Anti-Virus (http://www.grisoft.com). Version: 7.0.275 / Virus Database: 264.10.2 - Release Date: 10/8/2004