Special tests carried out by AB/PO from the tunnel in the converter in order to further study the fault in the FWD seen yesterday during the Fast Power Abort test (PNO.9)
While trying to ramp the converter up during the decay after a provoked fast power abort, the quench detector tripped and the quench heaters were fired. RQ5.L8 was going through the squeezing tests at the moment of the Q4 sporious quench, hence it performed a Fast Power Abort and its quench detector did not trip although it was at 3 kA.
Manual Squeezing tests repeated (PSQ). Test OK. It will not be considered as fully passed till it is done with the automatic function.
Fast Power Abort from PIC Test repeated after diode was repaired (PNO.9). Test OK.
RQ5.L8
Manual Squeezing tests (PSQ). Test OK. It will not be considered as fully passed till it is done with the automatic function.
RQ6.R7B1 and RQ6.R7B2
PCS test up to +10 A OK. The quench detector performed OK at this current level. There is a problem in the supervision that is being fixed. The transfer functions measured by AB/PO match very well the ones measured during ElQA tests.
Due to a missunderstanding with MPP and HCC, the circuit was powered up to 60A in order to check the crowbar. At 53 A, as expected, the QPS provoked a FPA that opened the switches. The procedure has to be reviewed since, so far, powering above 10 A is not allowed before carrying out PIC2. HCC will find an agreement by tomorrow between Mr Circuit, AB/PO and MPP.
ElQA RB.A78
At 600 V, with all the DFB instrumentation except the lead heaters disconnected, the resistance of the leads was 346 and 260 Ohms for 5 minutes which is a very promising result. Tests will continue tomorrow when 1.9 K are expected.
Planning for Tomorrow 06/06/2007
RQ4.L8
Powering at nominal plateau for some hours
If functions are available: Squeezing test
RQ5.L8
After modification in the quench detector: Fast Power Abort at nominal current (PNO.9)
If functions are available: Squeezing test
RD2.L8
Once new instrumentation is operational: Power to nominal current step by step.