FTOF – CABLE RUNS Joe Guerra

Terms/Definition FTOF – Forward Time of Flight PCAL – Pre-shower Calorimeter PMT – Photo Multiplier tube Panel 1A – Existing panel to be carried over from CLAS6. Panel 1B – New Panel comprised of 62 scintillators and 124 PMT’s. Sits +Z, directly in front of panel 1A. Panel 2 – New panel consisting of reused scintillators and PMT’s from the current panel 2 in CLAS6. Is comprised of 5 scintillators and 10 PMT’s.

Purpose This is to serve as a design document on the FTOF cable routing. In this document, thought process, idea’s, and criticism’s can be detailed on the routing of the FTOF cabling.

Design Considerations How to bundle and strain-relief the signal and HV cables along the sector frames for panel -1a and panel- 1b? Will all cables be the same length? How to strain relief the panel-1A cables and the PMT so that they do not put torques on the dividers? How to strain-relief the panel-1b cables at the PMT so that the connectors on the pig-tails are not stressed? How to strain-relief the cables at HV patch panels so that we have access for disconnects and so there are no stresses on the cables or connectors?

Design Considerations Will the cable runs go behind the frame beams or on the sides of the frames? Do we need to add additional places for strain- relief on either the panel-1a or panel-1b frames? How do we keep the cable bundles in position? We will need to make sure that we can get to the disconnect points of the panel-1b pigtails for servicing. We need to be able to read the cable labels at the PMT end and the patch panel end.

Design Criteria There are 62 PMT’s per each side of panel 1B. There are 23 PMT’s per each side of Panel 1A. There are two signal and one HV cables per PMT. HV Cables – 5mm diameter each Signal Cables – 4mm diameter each

AVAILABLE AREA’S

Area’s Available Between LTCC and Panel 1B – 2.480in²* Between Panel 1B and 1A – 6.448in² Between Adjoining Panel 1B’s – 4.308in² Between Panel 1A and PCAL – in² *NOTE: LTCC measurement not confirmed.

SPACE REQUIRED: PANEL 1A – Signal: 23 PMT’s * 2cables/PMT’s * 5mm * 5mm = 1150mm² = 1.783in²*** HV: 23 PMT’s * 1cable/PMT *6mm*6mm = 828mm² = in²*** PANEL 1B – Signal: 62 PMT’s * 2cables/PMT’s * 5mm * 5mm = 3100mm² = 4.805in²*** HV: 62 PMT’s *1cable/PMT’s *6mm *6mm = 2232mm² = 3.460in²*** ***NOTE: Required space estimated under assumption that there will be no bundling of cables.

AVAILABLE AREA’S Panel 1B – HV Cables Available:2.480in² Used: 3.460in² Panel 1A – Cables Available:13.785in² Used:3.066in² Panel 1B – Signal Cables Available:6.448in² Used: 4.805in² NOT USED

Cable Attachments/Relief Panel 1B- Top (HV CABLES)

McMaster Carr PN: 7572K13 Fabricated Bracket **NOTE: Brackets may be installed opposite of each other on opposite side of panel. This will be done for adjoining sector clearance.

Cable Attachments/Relief Panel 1B – Bottom (SIGNAL CABLES)

HV Patch Panels PANEL 2

Cable Routing -Panel 1A - Follows current routing plan

Cable Routing -Panel 1A/B-

Cable Routing -Panel 1B- Sectors 2 and 3

Cable Lengths

Answering Questions: Q: How to bundle and strain-relief the signal and HV cables along the sector frames for panel -1a and panel-1b? A:By using brackets, they cables will be routed either above and or below the prospective panel. Q:Will all cables be the same length? A: No. This would leave large lengths of cables of cables that would need to be handled/stored.

Answering Questions: (cont.) Q:How to strain relief the panel-1A cables and the PMT so that they do not put torques on the dividers? A: By running the cables in the same fashion that they are currently. Also, by securing them via zip ties to the panel 1A scintillator brackets. Q: How to strain-relief the panel-1b cables at the PMT so that the connectors on the pig-tails are not stressed? A: By using wire reliefs secured to the panel 1B backing structures.

Answering Questions: (cont.) Q:How to strain-relief the cables at HV patch panels so that we have access for disconnects and so there are no stresses on the cables or connectors? A: Attach the cables to the perforated tube steel that attaches to the Panel 2 Support frame Q: Will the cable runs go behind the frame beams or on the sides of the frames? A: Behind and in front of.

Answering Questions: (cont.) Q: Do we need to add additional places for strain-relief on either the panel-1a or panel-1b frames? How do we keep the cable bundles in position? A: Yes, we will add the holes onto 1B that are required for the bottom strain relief. We will use simple drilled holes and self tapping screws for attachment. The bundles will be held in position by friction due to the pressure from securing. Q: We will need to make sure that we can get to the disconnect points of the panel-1b pigtails for servicing. A: The pig tails will remain in front of the panel. After they are strain relieved and secured to the cable, they will then travel on the underside

Answering Questions: (cont.) Q: We need to be able to read the cable labels at the PMT end and the patch panel end. A: This will be done prior to installation via a sticker marking system.

Questions?