Introduction
The Decarad system was developed at JLab - it consists of 10 radiation detecting heads (geiger-mueller (GM) tubes) that connect (signal & HV cables) to a central box. That box has a board inside for changing the HV level and reading out the GM tube signals. The center box is connected to a digi port server via DB9 at box to RJ50 at the digi, which is then connected to the outside world via ethernet. The software uses the epics tool Stream with an asyn connection to the digi to send commands to the center box to read and write. The software is part of the RadiationMonitoring slac epics package.
Proposed names:
PV Name | Purpose |
---|---|
$(P):FIRM | read firmware number |
$(P):HRTBT | read heartbeat |
$(P):HVSTAT | read status of high voltage |
$(P):TEMP | read temperature of chassis |
$(P):HVMON | high voltage reading (V) |
$(P):HVSETPT | high voltage setting (V) |
$(P):RACK:Position | String to hold a description of the rack position |
$(P):nn:DoseRate | readback of dose from GM tube nn (01-10) in mR/hr (close enough, it saturates at xxx) |
$(P):nn:Position | string to hold a description of the position of GM tube number nn |
$(P):SEQ | sequence to readout the PVs at 1 Hz. The SEQ record has a delay of 0.06 seconds between sending 1 to each PV's PROC field so commands don't collide in the cable |
There are two sets of decarads (10 heads + central unit) so the PVs listed above are doubled and differentiated by $(P).
Suggested $(P) =
Cable Connection
Notes on cable connection (from email 8/12/21)
RJ50 cable/breakout (digiport server side) DecaRad Chassis DB9
Pins Pins
1 blue/wht TX- 2
2 org/wht RX- 8
3 org NC
4 green/wht NC
5 green TX+ 7
6 brown/wht RX+ 3
7 brown SGND 6
8 blk/wht NC
9 black NC
10 blue NC
Hardware Components
Using Decarad frame.pdf as the basic design
Thing | source | part number | Qty for 2 frames | total | |
---|---|---|---|---|---|
1.5x1.5" lite smooth 80-20 | tecotechnology.com prices from 8020.net | 1515-LS-96 | 10@72" 12@14" 12@24" | $7/foot comes to $700 | |
flange mount for caster to cross piece | tecotechnology.com | 2426 | 24 flanges 4*24 bolts/nuts | 24*$23 4*24*$1 = $650 | |
caster | teco tech | 2323 attach kit: 3110 | 24 4*24 bolts/nuts | 24*$30 4*24*$0.3 = $750 | |
5 hole tee plate for lower cross piece to vertical piece | teco tech | 4340 attach kit: 3320 | 12 | 12*$10 | |
7 hole corner between end verticals and first upper horiz | teco tech | 4352 attach kit: 3320 | 4 7*4 bolts | 4*$10.34 7*4*$0.77 = $65 | |
6 hole T to connect upper horiz with verticals in the middle | teco tech | 4310 attach kit: 3320 | 8 6*8 bolts | 8*$10 | |
4 hole corner bracket to tie decarad heads to - only need two bolts per | teco tech | 4301 attach kit: 3320 | 40 40*2 | 40*$5.12 40*2*$0.77 = $275 | |
teco tech total (bob's total was $1k) | 700+650+750+175+ 65+125+150=$2615 | ||||
wheel to hold 150' ethernet cable | 2 | ||||
75' retractable extension cord with 4 plugs | amazon | 2 | 2*$70 = $150 | ||
150' cat 6 ethernet cable | Bob says cablestogo | 2 | 2*$110 | ||
cart | mcmaster-carr | 2602T24 | 2 | 2*$283.23 = $575 | |
velcro zipties for decarads 15"long by 1/2" wide 5 for 9.73 green | mcmaster-carr | 6605K14 | 40 | 8*9.73 = $78 | |
velcro zipties for cables 11" long by 0.18" wide 10 for 8.39 blue | mcmaster-carr | 6605K13 | 50 | 5*$8.39 = $45 | |
DB9 male connector | L-com | C&P9M | 4 | 4*$1.10 = $5 | |
DB9 pins | L-com | CPM10 | 4 | 4*$3.91 = $20 | |
DB9 hood | L-com | SDC9AG | 4 | 4*$3.81 = $16 | |
L-com total | 5+20+16=$41 |
wheel for 150' cable: https://www.amazon.com/Woods-E103-Extension-Holiday-Storage/dp/B000E8SWQM/ref=sr_1_1?keywords=woods+e103+extension+storage&qid=1639714062&sr=8-1 (no longer available)
cabestogo 150 ft cat 6: https://www.cablestogo.com/product/43170/150ft-cat6-snagless-solid-shielded-ethernet-network-patch-cable-blue
black & Decker retractable extension cord 75' with 4 plugs: https://www.amazon.com/dp/B091GSSDVV/ref=sspa_dk_detail_3?psc=1&pd_rd_i=B091GSSDVVp13NParams&smid=A38BOHDI5WNXSO&spLa=ZW5jcnlwdGVkUXVhbGlmaWVyPUEyODdYUlUwRkFJNjFJJmVuY3J5cHRlZElkPUEwODM4MDIxMVhZNUFRMEhaS0Y2RiZlbmNyeXB0ZWRBZElkPUEwMTkyNjcxMUtPMFJOUUo1RkxZTiZ3aWRnZXROYW1lPXNwX2RldGFpbDImYWN0aW9uPWNsaWNrUmVkaXJlY3QmZG9Ob3RMb2dDbGljaz10cnVl
Ethernet cable length calculation: max(min(distance to nearest))+40' = 145' (CM33)
Quotes
Quote from Teco Tech:
Original Files
Files from Bob and JLab folks (2020, 2021)