Transcript Raggi_Lav261009x

Cabling and connectors for
future LAV stations
Mauro Raggi
LAV working group
CERN 26/10/2009
Cabling scheme signal
ANTI-A1
2 x DB37
32 ch In
FEE board
VME 9U
4x34pin scotch flex
64 ch out
10 x DB37
16 ch each
To be discussed with TDC
group
TELL1
4x128 ch TDC
32 ch IN
Robinson
Nugent 68Pin
Why DB37 connectors?
DB37 connection allows us to connect up to 16 ch in each connector including a
mass for each signal (need 10 connectors per flange for ANTI-A1 to A5)
This solution reduces the cross talk (see next slide)
16 ch modularity naturally matches LAV requirements in fact:
160 ch = 10 connectors (5x32 ch)
240 ch = 15 connectors (5x48 or 4x60)
256 ch = 16 connectors (4x64)
The cables are more flexible due to reduced number of coax line transmitted
Connectors easier to plug on FEE PCB
A firm (ECOVIDE) has been already asked for a cost estimate for a flange
housing 10 DB37 :
“Flangia DN 200 ISO-K in acciaio AISI 304L con 10 passanti Sub-Da 37 pin, leak
tested <5x10-9 mbar.l/sec” 4350.00 IVA esclusa.
The price is similar to the DB50 solution.
DB37 cabling solution
Connector 1
Connector 2
Present connection 50 pins
16 pins signal
16 pins ground (all connected)
16 pins signal
Connector 1
Connector 2
2x18 pins 2x18 pins
16 pins signal
16 pins ground
5 pins spare
HV connections
Present HV connections are OK for what concern modularity (32 ch/connector):
Connectors and feedthroughs are certified up to 1KV
Even if no discharge have been observed during test beam the dielectric material
could be damaged after long time due high voltage out of specs
Long term (10 y) behavior must be certified using termo-vacuum test under HV
Pump the system with flange to 10-7 mbar
Set the HV to 2000 V
Heat the system to 100 Celsius
Measure current discharge with a nano-amperometer
Check the vacuum with a vacuum leak detector
ECOVIDE propose connectors certified for 2KV but the cost is real high 2K€
(each)
The ground is now connected to the ANTI-A1 vessel.
The ground connection should be brought inside using some pins in the connectors
or a dedicated ground feedthrough
HV distributor
HV distributor can only provide a
500V range HV
Blocks HV spread is very near to
HV distributor range limit in red.
The maximum voltage is set to
1500V the minimum to 1000V
We are unable to switch Off most
part of the PMTs (only able to
reduce the gainto few 105)
HV cables have now 48 HV
channels connected but only 32
used. The remaining 16 ch remain
non terminated
Investigation needed to change
distributor output connector to
match our needs (if possible)
Custom power
only bus
5-8 FEE boards
7-10 free slots
Power Supply
TELL1
LAV VME 9U custom crate
5U
We are planning to project and build a 21 slots 9U VME mechanics crate housing:
5U
Power supply with custom power lines to supply the TELL1 and FEE boards
1U
TELL1 board
5-8U 5-8 FEE boards
7U
Still free could be used for clock and other services (need standard VME
bus?)
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