DEC RF30 Integrated Storage Element Service Guide

I have tried three different RF30 disks, two of them from one source and one all give me the same diagnostic error code, 0x300B, which seems to be too much of a coincidence, so I think it may be something in my configuration. I am using a MicroVAX 3800 (KA655 with KFQSA). When I power on, the fault light comes on and then goes out after a while. This I believe is normal behaviour. However, as soon as I try to access the disk (e.g. SHOW DEVICES in the console firmware) the fault light come on and when I boot to VMS (from a different disk), VMS can't see the drive. I thought it might be some kind of DSSI ID conflict because I have an RF72 in the machine at ID 0. Removing the RF72 does not change the behaviour. Installing an ID=0 plug on the RF30 does not change the behaviour. I set the DIP switches on the RF30s to have an ID=1 and still it doesn't work and PARAMS reports UNITNUM=0. I followed this page http://mcmanis.com/chuck/computers/vaxen/dssi-plug.html but it didn't work: PARAMS> sho /mscp Parameter Current Default Type Radix --------- ---------------- ---------------- -------- ----- MSCPNVR 2020202020202020 2020202020202020 2020202020202020 2020202020202020 2020202020202020 2020202020202020 2020202020202020 2020202020202020 String Hex RO UNITID 1502401193918703 0000000000000 Quadword Hex RO ALLCLASS 0 0 Byte Dec B MEDIAID 2264601E 2264601E Longword Hex RO U UNITNUM 0 0 Word Dec U FIVEDIME 1 1 Boolean 0/1 B FORCEUNI 1 1 Boolean 0/1 U FORCECID 1 1 Boolean 0/1 RO CNT_TMO 60 60 Word Dec RO PARAMS> set unitnum 1 PARAMS> set forceuni 0 PARAMS> write Failed to acquire unit, cannot WRITE Am I doing something wrong? Thanks Rob