How it works
- Interlock summaries:
modules that do analog/digital i/o for the 3 locations:
- Standby: Steps taken to go to
standby mode so you can bring up the high voltage.
- The green standby light is the dome HV ready and HV off.
- st.gen. is the 40 byte status block you can see in the misc
- _nn_mm nn is the byte in the misc screen, mm is
the bit mask for this bit
- schematics in volume 3.
Interlock summaries: (top)
interlock summary: st.gen.hvpsIntlkSum_27_80
- Set in software at stats9.c stats(). AND of the
door intlk */
- st.ttiDI.hvpsGndStKIntlk_19_10) /*
hvps gnd stick */
- not st.ttiDI.HVPsOilFlt_19_20
/* hvps oil fault*/
/* hvps gnd switch */
breaker proof */
- not st.ttiDI.hvps480VPhFlt_21_8)) /* hvps 480v phase
- (see also standby seq. it includes the filament on
- There is a hardware filament timer in the dome. It is
a oneshot on 190211-sh1 U14 the FO card.
- It starts counting when st.ttiDI.filTmrRlyCmd_9_10 is
- The relay command is true when the filament Voltage and
current proofs are true for both klys'
- It is set to count for 880 seconds. It is retriggerable if
it loses one of the proofs.
- Tracing the signal through the schematics:
- FilTmrRlyCmd to start the counting comes from up in the
- 190152 sh8 combLogic Chip U19
- 190223 sh1 shows chip with pinouts (pin 7 out)
- logic on 190362 shows which proofs it needs.
- 190223 sh1,N shows the driver after pin 7 on the
- comes down on tti3pin 13 (filTimerRlyCmd) sch
- Goes to one shot to start counting on 190211-sh1 U14
on fiber optic card.
- 190211-sh1 U14 FO Card has one shot.
- If filTimCmd loses one of it's proofs, it can
restart the 880 sec timer.
- There is a software timer in the cpu that counts down from
- The schematic calls it operations filament timer
- The flag is called filset. the counter is cntr.filTmr_c40
- It is counted down in the interrupt routine (18.2 hz) if
counter !=0 and filContProof is true.
- If filTmrRlyCmd is true and counter > 16380 set counter
to 16380. This causes the cpu counter to jump down to
15 minutes if the hardware timer has started and the cpu
timer is > 15 minutes.
- filset is set to 1 in interrupt routine when filContPrf
true and counter decrements to 0.
- It is sent to the dome on TTI_10 pin 06.
- The hardware timer and the cpu timer are anded to give
- 190152 sh8 or 190362 p27 fil timer complete ind. It
comes down on ttI_3 pin 14
- The hardware and software timer are part of the large and gate that is required
before the high voltage can come on.
- Debugging the timer:
- stats filTmrDone --> it is done and ok.. If not:
- stats bit4 filTmrRlyCmd make sure it is set. This
starts the counting
- If not look for stats klystron proofs V and I.
- Check computer counter40 for filament timer countdown.
- It needs filContPrf stats to decrement.
- When it hits zero, it sets the variable filset=1.
- If filset=1 then the computer filament timer done is
sent to the dome on ttiDO(10,bit6). This gets and'ed
with the hardware timer. (sch 190362)
- Check the hardware counter output. (shm 190152 sh 8
- This signal is also part of hv Ready that goes from the
dome to hvps via fiber.. (190362)
- If you are running and then the hv goes off and you have
to wait for the filament timer, then the system must have
lost one of the proofs for the filament current of Voltage.
There should be a fault flag if this occurred.
Keep Alive. (top)
The keep alive signal (watch dog timer) is
used to guarantee that the pc 723 program is still running.
The pc toggles a bit in it's interrupt routine (18 hz).
This gets sent to the HVPS and to the dome. This 10 pps signal goes
into a retriggerable one shot that has a time constant gt than
100 ms. The ok state for the flipflop output is 0 (set by reset). As
long as it gets retriggered every 100 ms, the one shot will remain
with a 0 output. If the oneshot output drops, then the following
edge of the D input will cause a 1 on the output (not ok). This will
shut down things. The keepalive report from the logic chips that use
the keep alive are sent back down via the tti digital inputs.
- newtick interrupt routine:
- cntr.aliveToggle_c16 (counter 16). gets toggled every 18
- This value is sent to the digital out of the dome and
HVPS. It is called keep alive or 10 pps.
- dome keep alive
- 723.c tto(10,7) to dome (schematic 190162 sh 6.xa10
pin 7). It is called 10pps
- To 1 shot on sch. 190208 via backplane TB1.
- Into one shot U1A (this failed on 08mar09)
- The one shot is set for a time constant gt 100 ms.
- As long as the keep alive pulse arrives at 10 Hz, the
one shot output will always be high.
- To A8 board 190152 sh 8. (board level schematic) ends up
in U19 pld for hv Ready...
- chip level on 190223 sh 2 p1-b32.
- Enter pld U44 on pin 41 then straight out on P77 (see
shm 190364 logic diagram). Not used on this chip.
- Then goes to U19 p51 . D input of flip flop (active
- The FF output is set low by the reset falling edge.
- It will stay low unless keepalive goes to 0 (we loose
- The FF output is inverted and sent to the dome HV ready
- If keep alive goes low, the Dome HV ready goes
- This Causes standby green light to go off
- drops the ground switch ssr which (i think) causes a
- brd A8. brd sch.
190252 (logic 190362 U19, 190364 U44)
- U19 pin 45 output (keep alive report)
- To U44. pin83 inp, out on P37.
- Inverted and output on p1-a21 (190223 sh 3.. you can
probe it here).
- Dome TTI digital input (190162 sh 3. xa3 pin 6.
- hvps keep alive:
- tto(13,13) hvps (schematic 190154 xa3 pin 13).
- to be finished...
Magnets don't turn on: (top)
Normally this is called from standby after the
cooling has started and the filament has been started
- To start need (assume kly1 in the examples):
- kly1 selected and don't have kly1 magnet contactor proof.
or missing magnet flow proof then go back and try restarting
- Send the magnet start command to hvps tto(13,9,1)
- doesn't look like this is in the database.
- 190154 sh-1 has the tti DigOut module . show Pn->Jn
which are flipped (see sh- 2-2)
- 190235 sh-3 has the pld chip with it's connections.
- 190374 has the logic diagrams of what the chip does. The
Pn are pin numbers
- Check that digOutput bit is getting to the power supply
building. In hvps: look at the front of the tti module:
- XA3 190154 bit 9. should be high
- Then bit9 -> p4-12(109154) to (190235 sh3) ->
J4-2 -> pin 59 of chip (190374 logic)
- the command gets anded with not kly1MagReady (p74 of chip)
that comes from upstairs).
- the comand then get sent out chip pin 27 v1 magnet
contactor ->chips -> J5-3 .. (190235 sh3,4)
- j5-3 -> p5-11 -> tb1-15 kly1magnet contactor ssr
- to be finished...
Body current (top)
The body current signal is generated up in the
- 190166. schematic diagram amplifier assembly. This is where
the body I signal originates.
- Each collector return goes through a separate resistor ( to
measure individual collector currents).
- These are then tied together and connected to the shield of
the triax cable that sends the return current down to the
power supply building.
- Two 8 ohm 30 watt resistors in parallel (r1,r2 on schematic)
connect the return to ground via two step down transformers
- They are used to measure the peak body current.
- They are sent to sh3 via A,B
- A separate measurement is made across the two resistors
R1,R2. It is used for slower body current measurements
- This is sent to sh 3 via C,D
- We have spliced the triax cable to a coax cable a 100 ft (?)
from the klystrons. At the splice the shield is shorted to the
cable return. So the designed function of the body current is
no longer the same.
- sh 1 (d6) body current kly1 .
- A,B peak body currents to sh 3. This is used
to measure fast arcs.
- C,D average body current. for slower things, gas,
mis focused magnets
- I don't see where this goes anywhere on sh 3. Looks like
it is connected to the shield of 4w27
- see maintenance manual pg8-24 section 8-5 for a
- The two circles (d6) are the triax cable. The inner
point is -63kv, the first circle is the return, the outer
circle is the shield.
- sh 3:
- Avg body current. Looks like it gets filtered .
- looks like it is connected to the shield of 4w27?
- peak body currents
- Connected to tb2 (pins 1,2) which go out 4W27 (called
body current A)
- also connects to tb5 (pins 13,14) which get sent out
- Connections between klystron and supervisory
- Note: cables outside the control cabinet are prepended with
4. cables inside the cabinet can have the same number but
without the 4.
- page 109109 schematic diagram transmitter room. Shows the
cable connections klystron to control cabinet
- 4A2 is the klystron, 4A1 is the control cabinet
- Peak Current A: 4A2_TB2 ->4w27 ->4A1J7
- Peak Current B: 4A2_TB5-> 4W28 ->4A1J8 (note typo on
schematic calling this J7).
- These go klystron to control cabinet
- See 190392 vol 4 parts list for the pin colors. the
cables are 20 feet long
- page 109144 schematic diagram dome xmtr control. Shows
cabling inside cabinet to system supervisory chassis.
- A4 is the system supervisory chassis
- PeakCurrentA on J7 -> W21 -> J21 on card A4A13
- A4A13 page 190152 sh3 is an analog processing board. it
creates the analog output for monitoring and the proofs
- PeakCurrentB on J8 ->W22 -> A4J22 on card A4A13
- A4A13 page 190152 sh4 is an identical analog processing
- See 190383 (vol 4 parts list) for the wire colors and
lengths (7 feet).
- see maintenance manual page 7-12 fig 7-3 (with a
- 190152 sh(3,4) system supervisory chassis.
- analog processing board.
- common board type for analog processing. board schematic
190205, layout 190204-1 (see assembly diagrams partslist
- sh(3) BodyCur A J21 p14.1 .
- sh(4) BodyCur B J22 p7,20
- The analog signal gets processed into:
- BodyCurA fault A4 digital input dome.190162 XA04
- BodyCurB fault A5 digital input dome 190162 XA05
- TTI analog input sent as body current meter value;
- BodyCurA A7 analog input 190162 XA07 pin 6+/-
- BodyCurB is not sent down.
- To straighten out:
- What is being done with avg body current?
- What affect does tying the shield to return have on triax.