NHC was entered on April 17, 2023 for inspection and maintenance. Summary :

Compressible and non-compressible waste was loaded into a 55 gal drum and removed from the NHC. This same drum will be inserted into the SHC at a later date to be sorted, compressible waste compressed, and drum filled more.

Manipulator remote end tong cables checked. Tong cables didn't show any wear but both east and west had tong cables had hopped off the third highest pulley (see detailed write up . This was fixed by tying the tongs in the closed position to provide slack in the cables then inserting a t-handle through the wrist and offering the cables back onto the pulleys. Cable hopping is most likely due to aggressive ratcheting and releasing of the tong during operation.

Manipulator booting flanges were removed from both manipulators as it was previously found that  the booting interferes with access to the inside of the containment box so it could not be used. Flanges were remove to provide even more clearance.

Containment box cover removal arm - linkage fasteners were removed one at a time and blue locktite added then reassembled and tightened appropriately to allow arm to swing freely (see detailed write up) . Lack of locktite during initial assembly was allowing fasteners that pass through bushings into the linkage arms to loosen over time/cycling.

Exhaust pre-filter changed.

Target insertion jig - The target insertion jig was rumored to had a missing fastener. A loose nut was found that appeared to belong to it but after much inspection a location for it could not be found...i.e. all parts appeared to be counted for. During this inspection it was noted that some over the fasteners in the main hinge were loose. Again these were removed one at a time, blue locktite added and fasteners tightened to allow proper movement (see detailed write up).

Window inspected for leak. No sign of any leakage from the "hot" side.

 TM4 with target TiC#5 installed has been leak checked and electric checked on NHC.

 TM4 with spent target TiC#5 electric check after moving from ITE to NHC.

 TM4 with new target SiC#45 installed has been leak checked and electrical checked on top of NHC.

The TiC#5 post irradiation inspection was done on Wed. June 14 and Mon. June 19. This target didn't have any obvious issues but it didn't produce much beam. The inspection revealed that the container was quite embrittled and showed significant damage, though it was not broken. The FEBIAD grid looked fine, despite the large anode current draw (indicating that current was flowing elsewhere). The gas line looked fine though the gas injection to this target looked as if it wasn't connected. But there was a plug on the unused line, so it must have been correct. No other obvious signs that would explain the poor performance. Pictures are can be found here https://documents.triumf.ca/docushare/dsweb/View/Collection-37913

 TM4 with spent target SiC#45 was disconnected ITE  and an electrical check made right after moved on NHC. 

 An electrical check was made after new target installed on TM4.

Looked at SiC#45 in the hot cell. Looked very clean, no deposits on the heat shield or other components. Target also looked very straight. Only issue we saw was sparking marks on the EE side that faces the ground electrode, in several spots. This target had a bout of sparking when ramping up the protons, so I guess that was the location. Will look for matching spark marks on the ground electrode next time TM4 is in the hot cell. Forgot to take picutres...

TM2 TiC#6 post run electrical check has been done at TCS. See attachment

Nb#10 has been installed on TM2 . electrical and leak check on HS line are good. See attachment.

PIE on TiC#6 was done in the NHC. The target assembly looked brand new when we took it out, no heating spots or deposits (pictures on docushare). Online we measured a 400kOhm connection between TGHT-TBHT-COIL to HV common (TGHT and COIL shorted in TM2 service tray) and anode was unstable above ~300V. After the module move and before the target removal David found TGHT-TBHT-COIL was a dead short to HV common and the anode was at 39kOhms to HV common.

1. Wanted to see if the TGHT-TBHT-COIL short was on the COIL. Measured with ohmmeter the COIL lines to HS and got about 700Ohms. But with the target lying down the COIL lines drop and touch the heat shield so to do this measurement Chad had to lift the lines, which could cause them to touch something else. So not sure how reliable this measurement was. It jumped around a lot, saw 0L occasionally.

2. Measured both target legs and tantalum gas line to HS, got about 5kOhms repeatedly using the ohmmeter.

3. Meggered across the gas line insulator to the gas line going into the target and got open circuit at 250V, so the gas line wasn't coated.

4. Target container looked vaguely red in the areas where the target material was, otherwise still no deposits on the inside. The container was not overly crystalized as seen on the legs and end caps.

5. Some sparking marks on the EE and some slightly asymmetric deposits

Continuing Aug. 22 2023:

6. Found what looks like a hole in the insulation on the COIL, maybe the cause of our short? Found a corresponding line mark on the copper plates that hold the coil down but not sure if it is related. Pics on docushare.

7. Grid looks perfectly new. Where was that current going?

8. Copper plates that hold coil were loose and bolts that hold coil in just fell out as well.

9. What can be seen of the anode wire looks good.

 TM2 with new target Nb#11 has been E/L checked sitting on NHC.

  TM4 with spent target UCx#42 has been electric checked at NHCpost right after transferred from ITE.

 TM4 with new target Ta#65 has been E/L checked at NHCPost.

 TM4 with new target Ta#65 has been E/L checked at NHCPost.

Nb#10target has been remotely  transferred from NHC to SHC. 

Update 2024-09-12: C. Fisher confirms this is actually normal behaviour. The Y-axis motion is inhibited when X and Z are in a certain configuration, which was true when the manipulator was mounted on the wall in storage position. Non-issue. A note about this has been made in the operator manual.

It was observed today that for the spare manipulator (Model N, Serial 9351), the Y-axis motion was not functioning. X motion and Z motion are functioning as expected. Note that the Y-axis linear actuator was recently replaced and successfully tested and has not been used since the replacement (see e-log 2422).

The following information was determined from troubleshooting:

• X motion functioning correctly
• Z motion functioning correctly
• Y motion selection functioning correctly - the indicator light on the operator control box lights up to confirm Y is selected, and the relay on the main control board which selects the Y axis toggles, as expected
• Y motion motor contactors do not function as expected when toggling in either direction. Note that these contactors are shared in common with the other two motion axes, so they are functioning correctly and presumably the motor controller itself is as well, since the other axes work.
• Most likely, because of the above reasons, there is an issue with the inhibit signal that is specific to the Y axis. The inhibit signal which runs from the main control board to the motor control board is shared in common with all motion axes (same for the two direction select signals). It is suspected (not yet confirmed), that the microcontroller is not outputting the inhibit signal as it should be. This is not due to a limit switch related issue because the Y axis does not have limits. Troubleshooting this has been difficult because the schematics do not show the full extent of the circuitry.

Further troubleshooting steps:

1. Check inhibit signal functionality - is it working for Y axis?
2. Check direction control signal functionality - are they working for Y axis?
3. Swap motor select wires to "trick" the microcontroller into thinking it is running a different motor, to further isolate the issue.
4. If required, swap the entire main control board with another manipulator's, to see if the issue is related to the circuitry which is not described in the schematics.

At the time, this issue is not deemed critical because this is a spare unit.

On Friday, September 6, 2024 Model 'N' remote arm #9352 was removed from the NHC right side installed position to investigate  an ongoing issue with the tong motion circuit (no motion on the remote side when handle on operator side operated).

Inspection revealed that the tong cable on this arm have hopped its cable drum and rapped around the shaft of the cable drum. As well, the tong cable had hopped a lower pulley and was jammed between the pulley and casting of the pulley housing. These issues were corrected and arm#9352 was reinstalled onto the right hand position. This repair resolved an ongoing tong motion system stemming from November 2023 described below.

initial tong motion problem from November 2023 when the tong system jammed, operator side arm #9763, remote arm #9342.

Remote arm #9342 was removed and replaced with arm #9352 as it was suspected there was a hopped cable on #9342. Upon removal it was confirmed the tong cable on remote arm #9342 had indeed hopped the pulley. After installation of the "spare" remote arm #9352 that hAd not been installed since previous servicing and should have been completely operational, it was found the tong system still did not work properly.

Upon thorough inspection of operator arm # 9763 it was found that the tong cable was prematurely reaching the end of its travel on its drum causing the inability to activate the circuit. The tong cable was reset on its drum as per manufacture's specs with one full cable rap on the drum and one full pretension wrap of the tong drum spring.

Although this resolved part of the problem and allowed a full squeeze of the operator handle it did not result in transfer of motion through the system to the remote end.

Further investigation continued, separating the operator side arm from the seal tube and testing the seal tube and operator side arm independently. Both systems worked fine independently, pointing to a potential problem between the seal tube and spring loaded coupler on the remote arm.

Remote arm #9352 was removed and couplers visually inspected and end of seal tube on the hot side was inspected and found that the pin in the end of the shaft on the tong circuit was not installed symmetrically which could cause uneven pressure on the spring loaded coupler of the remote arm. This pin was adjusted and all pins on the hot side of the seal tube were dimpled and loctite applied as a precautionary measure.

This still did not remedy the tong motion problem. These led to the September 6, 2024 removal and repair of remote arm #9352. This arm had previously been serviced by a CRL technician in December of 2017 and had not been installed or used since and should have been in operational status. It is still not clear why it was not.

Model N remote arm serial #9342 tong cable has been un-jammed from between pulley 3D (see picture) and casting (this is an ongoing issue with #9342 and 9352) and cable restrung and exercised to check motion. Tong system is now functional but exhibits excessive slack. Next step will be to check tension of the elevation/twist cables and adjust the pulley block if required (this pulley block houses both the elevation twist cable pulleys and the tong cable pulley 3D which is the site of the persistent cable hop)...I suspect adjusting the tension here will at least slightly improve the slack. In addition I will also investigate repositioning the tong drum screws (the procedure used to adjust the tong opening).

2 broken lights of NHC were replaced in Target Hall. see pics attached.