Subject: Shutting down and bringing up MACRO
Paolo.Lipari@lngs.infn.it
Date: Thu Oct 07 1999 - 05:02:49 EDT
In the morning of the 6th of october there was a major intervention
on the underground electric plant.
Because of this intervention we had to perform a shut-down of the entire
detector, bringing also down the acquisition computers VXMACA and VXMACB.
The intervention was scheduled for 9:00. We were notified at 10:20
to start the shut-down procedure.
The computers were brought down following the procedure as posted,
and all crates were shut down. This took approximately 10 minutes.
The work on the electrical system was concluded after approximately 5h30'
(the scheduled time was 4h).
When the detector was turned on, as expected a number of problems
appeared.
For the scintillator system:
4 PHRASE power supply broken (we have no spares now!)
1 TOHM kinetic 1502 power supply broken
5B11 has a very high trigger rate for TOHM (disconnected)
WFDs on SM1 no longer received the Stop signal.
The last one is the most serious problem...uVax1 is out
of acquisition and we are going to work on it (we hope to
solve the problem as soon as possible).
For the streamer tube system:
Two splitter board were faulty
One : mVax 1, M3H9-10, S2W wires, Rack 19 had three dead channels,
it was replaced with a spare and tested as OK.
A second: microVAX 2, M7H1-3, Rack 55 had a dead channel,
it could not be replaced because of the lack of a spare.
It was repaired this morning (7th oct), during the running,
and is now working again.
Also a slow wire chain A1W1-6 does not shift at all.
A fixing of this problem requires use of the "passarella"
that is broken.
Some wires chains on M1 have problems with the slow chains occasionally.
There is also a Bari trigger channel that appears to be dead
M11H2 (the STAS and QTP are present for the channel).
Two CAEN-HV channels show voltage 100 V below the set values.
(there were several more, the problem hopefully will
cure itself).
We resumed the running at 16:17 with mVax 3,4,5,6.
The run was interrupted after 45minutes because of a broken power supply
(the run also had a number of other problems)
At 17:21 a new run was started with mVax 2,3,4,5,6
(mVAX 1 out OF ACQ) that continued normally (for 5.8h,
main problem a very high rate of ERP GC triggers on the south face).
Ioannis Katsavounidis
Nicola Zaccheo
Jan Reynoldson
Brajesh Choudhary.
Paolo Lipari
This archive was generated by hypermail 2a24 : Thu Oct 07 1999 - 05:03:11 EDT