Transcript 2015020ーFADC_Hybrid_cablesx

FADC/Hybrid cable production
21 Jan 2015
T. Tsuboyama
Situation
• Hybrid cable: From Hybrid (FR4 or Origami) to the DOCK
box inside the Belle II structure.
• FADC cable: From DOCK to FADC on top of the Belle2
structure.
• The budget for the FADC and Hybrid cables expires at this
March. We have to finish production by then.
• We have all cables and connectors.
• Tentative specification is set.
• I asked the company to produce 10 cables.
• Depending on the result, I will propose the final
specifications.
Electrical test
• The following test will be done by the company
• Conductivity can be measured with 0.01 Ohm precision.
• HV duration: Only 1 wire in the hybrid cable is connected
to the common ground level and voltage difference with
other wires will be around ±50 V. So I chose 200 V for the
test. The leak current or resistance is will be measured.
• Insulation: Not only the cable dielectric but also the
quality of connector assembly can be monitored.
• We will set the upper or lower limit values after the first
10 cables will be assembled and tested.
Hybrid cables
• Parts:
– The half-pitch, half-twisted and half-loosened Polyethylene or
Polyolefin cable, as known as the thin-SCSI cable.
– The production is discontinued in Europe, Japan and US, however,
HEPHY group knew CERN has some stock. They bought the cable
and sent to KEK.
– JAE connectors and SAMTEC connectors are more or less on the
catalog.
• The pin-clamping machine, so called “the applicator”, will
be delivered soon to the company. The production will
start then.
• Layer 3 cables will be prepared in HEPHY not by KEK.
FADC cables
• Using the 3D CAD data, Markus decided the length to be
12.5 meter, however, I added 0.5 meter for the case.
• The connectors are assembled at the flat part on both
ends.
• Flat part appears every 25 ±1.3 cm. For the 13m long
cable, the length tolerance will accumulate to 60 cm. It
means we can not make the length more precise than 25
cm.
• Markus accepted this condition from viewpoint of
electronics.
• I ordered the production of the first 10 cables.
• Final specification is set after examine the result.
Summary
• FADC and Hybrid cables should be produced by end of
March.
• First 10 samples will be produced, tested and shipped to
KEK.
• Specification will be settled and full production will be
done.