TM3 has been moved from the target conditioning station to the south hot cell.

TM3 was moved from the Silo to South Hot Cell.

TM3 was moved from the SHC to the TCS (no target installed).

TM3 was moved from SHC to NE silo. Cable tray was recently installed.

TM3 has been moved from the Middle-East silo to the South Hot Cell.

TM3 has been moved from the South Hot-Cell to the Middle-East silo.

TM3 has been moved from the South Hot Cell to the Conditioning Station. No containment box.

TM3 was remotely moved from the conditioning station to the South Hot Cell. No containment box.

TM3 was remotely moved from the South Hot Cell to the conditioning station. No containment box.

Please see attachment for TM3 May 1-15, 2017 Tentative Schedule at the SHC and TCS.

A video inspection of the lower service tray was performed this morning. Camera was inserted upwards into the service tray/service chase from the containment box. One potential spark mark was identified as well as epoxy not flush with insulator. Fiberglass does not extend into service tray/chase much and does not look, from initial inspection that it will be too difficult to remove.

Video can be found in docushare Document-142295

chad fisher wrote:

A video inspection of the lower service tray was performed this morning. Camera was inserted upwards into the service tray/service chase from the containment box. One potential spark mark was identified as well as epoxy not flush with insulator. Fiberglass does not extend into service tray/chase much and does not look, from initial inspection that it will be too difficult to remove. Video can be found in docushare Document-142295

 The attached picture is from the video: showing the fiber glass inside the Service Tray.

Found spark signs on TM3's containment on the side of the water blocks. They may be OLD or/and NEW sparking signs, but this in not determined at this moment. Please see picture: first attachment. First and second attachment show the profiles of water block and HV lines.

Today a HV test at atmosphere was performed for Each Line(s), while floating the other lines. THIS TEST AT ATMOSPHERE IS THE FIRST ONE AFTER THE FIBER GLASS WAS REMOVED.

Please note:

a). the Einzel Lens line (Y) was grounded.

b). after the fiber glass was removed the "R-U COIL" line and the "(F) Plasma" (which is the Anode line) were shorted to the BIAS voltage.

Tests performed:

1. Applied up to 32kV to "(A) OVEN -"

Sparks occurred at 32kV between the Extraction Electrode holder and the Ground Electrode.

2. Applied up to 33kV to "(B) OVEN +"

Sparks occurred at 33kV but we could not identify the spark location.

3. Applied up to 31kV to "(C) TUBE -"

Sparks occurred at 31kV between the Extraction Electrode holder and the Ground Electrode, at the top and the bottom.

4. Applied up to 30kV to "(D) TUBE +"

Sparks occurred at 30kV between the Extraction Electrode holder and the Ground Electrode, 2 spots at the bottom.

5. Applied up to 30kV to "(P-Q) COIL +"

Sparks occurred at 30kV between the Extraction Electrode holder and the Ground Electrode, all around.

6. Applied up to 30kV to "(R-U) COIL -", to "(F) Plasma" the Anode, to "(E) Cavity" or MSP, "(G) Gas", and  "(J) Heat Shield" - all these are "connected" together at the BIAS voltage.

Sparks occurred around 29-30kV at the Extraction Electrode holder and the Ground Electrode, at the bottom.

8. Applied up to 23kV to "(I) EE" - this is for the Extraction Electrode.

Sparks occurred at 23kV again at the same spot near the bottom, between the Extraction Electrode holder and the Ground Electrode.

Today a HV test at atmosphere was performed for Each Line(s), while floating the other lines.

Please note the Einzel Lens line (Y) was grounded.

Tests performed:

1. Applied up to 29kV to "(A) OVEN -"

Sparks occurred at 29kV at the Fiber Glass inside the Service Tray; and at the right side at the lines wrapped in Fiber Glass.

2. Applied up to 29kV to "(B) OVEN +"

Sparks occurred at 29kV at the Fiber Glass inside the Service Tray.

3. Applied up to 6-7kV to "(C) TUBE -"

Could not identify the sparks; it was a continuous discharge.

4. Applied up to 6-7kV to "(D) TUBE +"

Sparks/discharges occurred at 6-7kV at the Fiber Glass on the right side at the lines wrapped in Fiber Glass. We had to turn OFF the lights in the Hot Cell to identify the small sparks.

5. Applied up to 4kV to "(P-Q) COIL +"

Discharge occurred at 4kV. Could not identify it.

6. Applied up to 29kV to "(R-U) COIL -"

Sparks occurred around 27-29kV at the Fiber Glass inside the Service Tray; and at the right side at the lines wrapped in Fiber Glass.

Tom saw a spark at 27kV between the Extraction Electrode holder and the Ground Electrode.

Saw also a spark at the Ring Alumina insulator in the Service Tray, located on top of the second comb insulator with Epoxi.

7. Applied up to 27kV to "(E) Cavity or MSP, (G) Gas, (J) Heat Shield" - all these are connected together at the BIAS voltage.

Sparks occurred at 27kV at the Fiber Glass inside the Service Tray.

8. Applied up to 23kV to "(I) EE" - this is for the Extraction Electrode.

Sparks occurred at 23kV again at the same spot near the bottom screw hole, between the Extraction Electrode holder and the Ground Electrode.

9. Applied up to 27kV to "(F) Plasma"- this is for the Anode.

Sparks occurred at 26-27kV again at the same spot near the bottom screw hole, between the Extraction Electrode holder and the Ground Electrode.

Please see the first two pictures of the HV test at atmosphere done on April 19.

First picture shows a big spark between the Extraction Electrode mounting plate holder (at HV) to the Ground Electrode. Please note minimum gap between these electrodes is 7.8mm.

However the biggest visible spark was noticed at the bottom screw hole. (It is difficult to determine if at the 7.8mm gap were concomitant sparks occurring.)This spark started at 22kV and became stable above 24kV.

On April 20, 2017 Chad inspected this area with the Hot Cell camera and found a spark mark on the Extraction Electrode holder plate at the bottom screw hole. See the third picture.

Again it is very difficult with the existing Hot Cell cameras to inspect the areas where the gap is small (at 7.8mm gap between the conical surfaces of the Ground Electrode and Extraction Electrode holder)

In the second picture there are 2 small sparks: one on the top and another one on the right side at the lines wrapped in Fiber Glass. These sparks started at 20kV.

On April 21 the HV test was repeated with the Containment box ON and the sparks occurred again, at the same locations and at the same voltage.

I did a HV test on TM3 at TCS yesterday. HV Ramp up speed: 1KV per 5 minutes when below 30KV,1KV per 10 minutes from 30-36KV. There is no major spark below36 KV .  I could see  lots small and big vacuum response on IG1 and PNG2 when conditioning from 30-36 KV, especially when closing to 36 KV.  However, At 36.4 KV, There is a big continuous spark occurred. It could not be stopped until I lowed the HV to 14KV. I have to ramp up from 14 KV again.  This behavior on TM3 HV test is same as before we saw. The module can not pass 36KV at present condition.  During the test., EL is tied to 60KV bias. The HV cover on TM3 top is installed. And, Service tray  cover plate is installed on TM3.

Today TM3 HV conditioning went up to 65kV. I'll leave it here over night. ISAC OPS have instructions to keep an alarm on the HV, and ion gauge and turbo pump (TP2 tripped 3 times due to sparking).

Today TM3 was conditioned up to 50kV. At 50kV sparking started and to go higher in voltage it needs more conditioning time. Lowered it to 49kV for the night.

The TM3 containment box has been installed onto TM4. No issues, leak checked ok.