350MHz RF Waveguide Air Personnel Safety System Dave Bromberek March 3, 2008.

350MHz RF

Waveguide Air Personnel Safety

System

Dave Bromberek

March 3, 2008

2

Outline

System Operation and Layout

Failure Modes

3 Year Calibration

3

System Operation

Pressurization of the 350MHz waveguide system in Bldg. 420 is used as THE means of providing rf radiation personnel protection in the event of a breach of the waveguide system (see also technical note “Measurements of RF Power Radiated From Open WR2300 Waveguide Flanges” – D.Horan 7/3/05).

Blowers on the rf cavities provide cooling air to the input couplers and also slightly pressurize the waveguides to ≈ 3-4”H2O (≈ .1-.15 psi.). The pressure is monitored and interlocked by eight waveguide photohelic pressure gauges, one or more of which is capable of detecting a waveguide flange gap of .185”, in all available waveguide switching modes.

A trip of any waveguide photohelic will shutdown all five 350MHz klystron stations.

Orphan photohelics are installed at RF1 and RF3 to provide protection in these areas when the stations are switched off-line.

Additional photohelics monitor cavity blower pressure (Not Interlocked).

4

System Layout

Two blowers supply cooling air to the input coupler and slightly pressurize the waveguide.

Each cavity’s blower manifold is monitored by a photohelic.

Cavity blower pressure is alarm only

Each sector’s waveguide is monitored by a photohelic.

Waveguide air pressure is a PSS interlock and will trip all 5, 350MHz rf stations.

StaticAir

Pressure~4"H2O

To Waveguide AirPhotohelic

Bldg. 420Waveguide

Blower Air In

Blower Air In

InputCoupler

To Cavity Photohelic

B1 B2

Exhaust Air Out

120VAC CKT 1 120VAC CKT 2

Waveguide Air Thermocouple

IR

IR

5

System Layout

RF1 RF2 RF3 RF5 RF4

C1 C2 C3 C4

B1

B2

B1

B2

B1

B2

B1

B2

C1 C2 C3 C4

B1

B2

B1

B2

B1

B2

B1

B2

C1 C2 C3 C4

B1

B2

B1

B2

B1

B2

B1

B2

C1 C2 C3 C4

B1

B2

B1

B2

B1

B2

B1

B2

Sector 36 Sector 37 Sector 38 Sector 40

C1 C2 C3 C4

B1

B2

B1

B2

B1

B2

B1

B2

BoosterInjection

BoosterExtraction

To TestStand

P P

PPP

B1

B2

P

Cavity Blowers & Manifold

Photohelic Pressure Sampling Port

Transmission Waveguide & Air Path

P

PP

6

System Layout

There are two blowers on each rf cavity, one being redundant. The cavity photohelics are on a scale on 0” – 10”H2O and read 10” or better with both blowers at full speed.

Blowers are fed from two 120VAC power circuits/sector. Each cavity blower pair is fed from a separate circuit.

7

System Layout

Waveguide photohelics are on a scale of 0” – 5”H20 and normally read between 3” - 4.5”H2O.

Pressure sampling port is located on a section of waveguide in Bldg. 420 (see drawing)

8

System Layout

Photohelic gauges are individually fused.

A 24VDC power supply feeds the setpoint contacts from the cavity gauges to Allen/Bradley

Fuse

24VDC Power Supply

9

System Layout

10

Blower Control Screen

From RF Panel – Select Sector

Cavity Photohelic Setpoint Contacts

Blower AC Power Circuits

11

RF6 Waveguide Air PSS Screen

From RF Panel - Misc/Tools

12

OAGapps Data

From x-term type OAGapps

13

OAGapps Data

14

OAGapps Data

15

OAGapps Data

16

OAGapps Data

17

Failure Modes

Cavity Blower Alarm Check locally Dead or dying blower

8” H2O Check OAGapps

Symptoms Steps Problem

18

Failure Modes

Cavity Blower Alarm Check locally 2 dead blowers

0”H2O Check RF6 Hose disconnected

Check OAGapps Bad Gauge

Symptoms Steps Problem

19

Failure Modes

Cavity photohelic hoses CAN be disconnected and connected to an adjacent gauge to eliminate the photohelic as the culprit.

NEVER disconnect the waveguide photohelic hose unless the rf stations are already down due to a WG Air PSS trip.

If it is determined that a waveguide photohelic is the problem, or the system is tripped on waveguide air, a work request and CCWP must be submitted and approved.

C1C2

C3C4 WG

20

Failure Modes

4 Cavity Blowers in Alarm Check 24VDC P.S. Power supply

10”H2O

Symptoms Steps Problem

21

Failure Modes

4 Cavity Blowers in Alarm Check OAGapps AC Power

0” or Low “H2O Check AC Power breakers

Waveguide Air Trip

Symptoms Steps Problem

22

Failure Modes

Waveguide Air Trip Check waveguide integrity Any of these

0” or Low ‘H2O Check for hose disconnection

Gauge

Symptoms Steps Problem

23

3-Year Calibration & Testing

See “Technical Note on the Testing of the 350MHz Waveguide Air Personnel Safety System” – D. Bromberek 10/21/05

Test and adjust setpoints

– Requires the opening/closing of five waveguide flanges (one at each station), in twelve waveguide switching modes – 60 iterations

– Data is recorded and setpoints chosen• .185” uniform gap in a waveguide flange trips RF6 PSS System• .185” gap is detected by at least one photohelic in every

waveguide configuration• Loss of one cavity blower does not trip the PSS• Loss of two cavity blowers does trip the PSS (Not always possible)

– Validation and sign-off of CCWP requires tripping each of the eight waveguide photohelics one at a time, and verifying that it trips ALL FIVE STATIONS.

24

3-Year Calibration & Testing

.185” Spacers

.185” spacers in use

25

3-Year Calibration & Testing

Flange #314 @ RF3

0

0.5

1

1.5

2

2.5

3

3.5

4

4.5

5

No

rma

l RF

3O

rph

an

Op

en

RF

3 O

rph

an

No

rma

l S3

6

Op

en

S3

6

No

rma

l S3

7

Op

en

S3

7

No

rma

l S3

8

Op

en

S3

8

No

rma

l S4

0

Op

en

S4

0

No

rma

l In

j

Op

en

Inj

No

rma

l Ext

Op

en

Ext

1 1/4-2/3-5

2 2/3-4-5

3 1/4-3-5

4 1/4-2-5

5 1-2/3-5

6 1/4-2-3

7 2-4-3

8 1-2-3

9 1-2-5

10 3-4-5

11 2-4-5

12 1-3-5

Data Collected @ RF3 – May 2005

26

3-Year Calibration & Testing

Flange #314 @ RF3 Min/Max/Avg RF3 On-Line SR Modes

4.15 4.30 4.203.90 4.05 3.95

1.45 1.55 1.50

3.45 3.60 3.503.70 3.703.70

0.00

0.50

1.00

1.50

2.00

2.50

3.00

3.50

4.00

4.50

5.00

Low High Avg

" H

2O

RF3/S37 Normal Pressure

S37 -1 Blower

RF3/S37 .185" Gap

S37 -2 Blowers

S37 Setpoint

Simplified Data From RF3 – May 2005

27

3-Year Calibration & Testing

Calibration due spring shutdown ’08.