Here are the correct settings for JMRI and jumpers for the NCE Power Cab and NCE SB5.

It also explains how to read the version of your NCE USB . Only the first digit counts; the last three digits report how your jumpers 2-4 are set and jumper 1 is ignored on all systems.

Power Cab Instructions
=================
The correct settings for a Power Cab V1.65 or V1.28 (as shown when the Power Cab starts up) and an NCE USB V6 (or you are not sure of the USB version) are:
-- All USB Jumpers off (or at least 2, 3 & 4. Jumper 1 is ignored).
-- JMRI preferences are:
-- System manufacturer: NCE
-- System connection: NCE USB
-- Serial port: <whatever is appropriate for your system>
-- USB version: V6.x.x
-- System: PowerCab
-- Additional Connection Settings checkbox ON
-- Baud rate: 9600.

The JMRI console log should then report V6.3.0.

If it reports V7.3.0 and your Power Cab is V1.65, use the settings below instead.

The correct settings for a Power Cab V1.65 and an NCE USB V7 are:
- All USB Jumpers on (or at least 2, 3 & 4. Jumper 1 is ignored).
- JMRI preferences are:
-- System manufacturer: NCE
-- System connection: NCE USB
-- Serial port: <whatever is appropriate for your system>
-- USB version: V7.x.x
-- System: PowerCab
-- Additional Connection Settings checkbox ON
--- Baud rate: 19200.

The JMRI console log should then report V7.3.7.

SB5 Instructions
============
The correct settings for an SB5 and an NCE USB V7 are:
-- USB Jumper 4 on. All others off (or at least 2 & 3. Jumper 1 is ignored).
-- JMRI preferences are:
-- System manufacturer: NCE
-- System connection: NCE USB
-- Serial port: <whatever is appropriate for your system>
-- USB version: V7.x.x
-- System: SB5
-- Additional Connection Settings checkbox ON
-- Baud rate: 19200.

The JMRI console log should then report V7.3.1.

If the system does not work after this and your USB is V7:
-- If your SB5/Power Cab is V1.65 rather than V1.65B, you may have been affected by a firmware issue (triggered by a System Reset).
-- Your NCE USB may be set to a bad cab address.

In either case, go through the following :
-- Quit JMRI.
-- Ensure neither LED on the NCE USB is stuck ON. If so, power cycle the USB by unplugging it from the cab bus cable.
-- Ensure you have no other throttles connected.
-- Restart JMRI and immediately go to Configure USB Interface under the NCE menu.
-- Set the Cab ID to 3.
-- Attempt a JMRI operation (use a throttle, Identify a decoder.
-- The status line should stay green and it should work
-- If this does not work, do not fiddle with any other settings but instead:
-- Observe whether the Cab Bus LED on the NCE USB is stuck on and report back.
-- Use Help->System Console...->Copy to clipboard and paste into a post for us (or an offline email).

Courtesy Dave Heap in Australia and NCE Yahoo Group https://groups.yahoo.com/neo/groups/NCE-DCC/info