An A319 GEN 1 Fault at FL340 would not reset. The APU was started and the generator assumed the AC bus 1 load.

Narrative

Accepted a short-call; early morning; Junior Assignment; rushed to the airport; and departed 12 minutes late (and all the typical craziness that accompanies such a start to the day). During climb phase and approximately FL340 we observed 'flickering' of all screens on forward instrument panel accompanied by the sound of relays clicking behind us; a slight rudder 'bump'; and shortly thereafter received and ECAM 'ELEC GEN 1 FAULT'; and associated chimes. Pilot flying called for ECAM actions which essentially involved attempting a simple reset of the GEN; which was unsuccessful. ECAM then had us turn off the affected GEN. Pilot flying suggested starting the APU; so I turned on the APU master switch; but decided to check the limitations on the service ceiling on the APU; before starting. Flight attendants called to inquire about loss of power. After finishing that call; I pulled out the FOM to perform the paper procedure (almost a duplication of ECAM- with the exception of the statement 'NOTE: If available; the APU may be started; and the APU GEN used.') After confirming the APU service ceiling was 39;000 FT; I started the APU; which started and ran normally; and took over the electrical load of the failed GEN 1. Called flight attendants and confirmed/reassured their electric was restored. While I was re-filing my manuals; I reviewed the entire APU limitations section again and realized we possibly had unknowingly started the APU above the starting altitude limit of 25;000 FT (which; by the way; is listed on the line AFTER the max operating altitude.) The APU started normally and I monitored its entire starting sequence; which was always within normal ranges. There was no indication of damage to the APU or related systems. The remainder of the flight was uneventful.1. While I might now wish I had all the (non-memorization-required) limitations memorized; I don't believe that is possible (where do you stop?) or even desired; and still may not have prevented the situation; 2. Revise the statement 'NOTE: If available; the APU may be started; and the APU GEN used.' To be accompanied by a statement referring the reader to APU limitations in section 2; instead of 'leading' the reader to an action he/she may not want to take right away. (In short; don't suggest starting it in a procedure without a reminder of where and when it should be started.) 3. List the APU operating envelope limitations in a logical order; instead of haphazardly; such as in order of ascending altitude; so that applicable limitations are more easily recognized and can be referred to quickly without having to read the entire section during a time crunch.