Tag Archives: 16-020

16-020/050 Heat Exchanger Shuts Off

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The X-ray sources used on the older Physical Electronics (PHI) XPS systems use a heat exchanger which circulates air-cooled water to keep the X-ray source from overheating. 

If your 16-020 or 16-050 heat exchanger shuts down there are only a few things that can cause that issue.  This blog post will explain how to isolate the problem.

The 32-095/96 X-ray source control has two interlocks that will shut down the heat exchanger. The first is a vacuum interlock that connects from J2 interlock on the back of the 32-095/6 to setpoint 3 in the DGCIII ion gauge. That set point is typically set to 5 X 10-7 Torr.   To bypass the vacuum setpoint, turn off the 32-095/6 main power and remove the J2 cable on the back of the 32-095/6, then short out pin A to B on the connector (not the cable) with a small paper clip.   Note that with the vacuum interlock cable bypassed there is no protection for the x-ray source if the vacuum pressure gets too high (as in if the system vents).

If the 16-020/050 heat exchanger no longer shuts down then the issue is related to setpoint 3 on the DGCIII. It could be that the J2 cable is loose or that the setpoint relay in the DGCIII is dirty. Here is a blog post on how to clean the relays – https://www.rbdinstruments.com/blog/dgc-iii-digital-ion-gauge-control/

The second 32-095/96 interlock is the flow switch.   If the water flow is insufficient then the flow switch will turn off the 16-020/050 heat exchanger. It could be that the actual flow is low, or it could be that the flow switch is defective.  If your heat exchanger has a flow meter then you can see what the flow is. If you have an 04-548 source then the flow rate should be about 1.7 GPM (gallons per minute).  If your system has a 10-560 source then the flow rate should be about .9 to 1 GPM.  If you do not have a flow meter, then you need to remove the X-ray source lines from the source and run the water into a clean container (so that you can reuse the water) for a total time of 1 minute.  With the water lines disconnected from the X-ray source the heat exchanger will shut off after 9 seconds. You need to turn the 32-095/6 off and then back on to get the water flowing again.  One you have 1 minutes’ worth of water, measure it and then you will know the GPM.  Then put the water back into the heat exchanger.

If the GPM is low, then you may have some obstruction, or the deionizer cartridge or particle filter may need to be replaced (RBD Instruments provides them). If the water lines are green or black, they should be replaced. Here is a blog post that explains how to do that – https://www.rbdinstruments.com/blog/replacing-the-water-lines-in-a-16-050-heat-exchanger/

If the GPM is correct, then you can bypass the flow switch by turning off the 32-095/6 and shorting pins A to E on the Pump Control connector (not the cable).  You also need to move the Pump power cord on the back of the 16-020 to the HV power receptacle and then the pump will turn on when the circuit breaker in the back of the 16-020 is turned ON.   Remember that there would be no protection for the source if a water flow issue develops while the flow switch is bypassed.   If the heat exchanger does not shut with the flow switch bypassed then the issue is related to the flow switch.  It may need to be adjusted, or it may be defective.

To adjust the flow switch setpoint, turn the small, slotted screw that is inside the hole in the black housing 2 turns CW.  Then see if the heat exchanger stays on.  If not, try 4 turns in the other direction.  If the heat exchanger still turns off, then the flow switch is bad.

RBD Instruments provides a flow switch and a power converter. The original flow switch was powered by 120 or 220 VAC, the new ones are 24V DC.

To order a flow switch kit that includes the power converter contact us here –

https://rbdinstruments.com/phi/optics-parts.html

Here is a link to a procedure on how to replace the flow switch – https://www.rbdinstruments.com/blog/tag/replace-flow-switch/

16-020 heat exchanger 12″ deionizer cartridge issue

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The 16-020 heat exchangers are used with the older Physical Electronics (PHI) 5100 through 5400 X-ray photo-electron spectrometer (XPS) systems.The 16-020 has a built-in deionizer cartridge (and a particle filter) which keeps the water in the closed loop system clean and it also keeps the resistance of the water high. 

The original deionizer cartridges were blue and had a recess in the bottom of the filter that matched up with a plastic guide on the bottom of the Millipore housing.  Those blue deionizer cartridges are no longer available. The new replacement deionizer cartridges do not have a recess on the bottom.

When a new deionizer cartridge is used with the original Millipore housing the plastic guide on the bottom of the housing will push up on the bottom of the deionizer.  This makes it difficult if not impossible to fully screw on the housing.  It also puts pressure on the bottom of the deionizer cartridge which can rupture the bottom of the deionizer and cause the media particles to leak out, potentially causing an issue with the water flow and or damage the pump and lead to a catastrophic anode melt down. There are two ways to solve this fit issue. One is to cut and grind out the top part of the guide on the original Millipore housing. To do that you need to remove the plug on the bottom of the housing and then use a drill or cutting wheel that is mounted on a drill extension. The pictures below show a housing before and after modification.

 

The other option is to replace the original Millipore housing with new housing that correctly fits the new deionizer cartridge. But if you replace the housing you will also need to replace the manifold as the new manifold will not fit into the original Millipore manifold.

RBD Instruments provides both deionizer cartridges and housings. If you have the original Millipore housing on your 12” deionizer cartridge then I recommend that you inspect it to see whether the guide on the bottom has been cut down or not.  If not, you should cut it down or replace the housing.  

If the deionizer is ruptured then the entire cooling system (reservoir, pump, water lines and source) needs to be inspected and flushed out.This problem is an issue only with the 12″ deionizer cartridge on the 16-020 heat exchangers. 

The 16-050 heat exchanger that is used on the 5600 and up XPS systems has a 10″ deionizer cartridge.

Not sure if you need to replace your deionizer cartridge?  Just run up the high voltage on your X-ray source to 15kV but do not set an power to the X-ray source.   Observe the emission current reading on the HV supply.  If the deionizer is good the reading will be 1-2 mA.  Once the leakage current gets up to 3-4 mA at 15kV you should plan on replacing the deionizer cartridge and particle filter soon.  If the leakage current at 15kV is 5 mA or higher you should replace the deionizer and particle filter and also flush out the water with new distilled water from a grocery store.  Lab distilled water does not always work but grocery store distilled water works every time.

Contact RBD Instruments to order the deionizer and particle filter.

Deionizer flow restrictor

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Deionizer flow restrictor for PHI X-ray source heat exchangers

This post is a reprint of a tech tip that we published in our fall 2008 Service Detail newsletter. This exact problem came up recently and so I thought I would resurrect this tech tip for educational purposes. In the recent case we knew that the leakage current was very high and it had been several years since the deionizer cartridge was replaced. Replacing the deionizer cartridge was the logical solution. Replacing the cartridge did solve the problem for a while, but within a very short time the leakage current problem returned. Cleaning out the flow restrictor as described below solved the problem.

If you need replacement water filters or deionizer cartridges for your PHI 16-020 or 16-050 X-ray source heat exchangers that are available at this link – PHI Optics Parts

Deionizer flow restrictor inspection and cleaning procedure:

The 04-500 and 04-548 15kV dual anode x-ray sources are water cooled by a closed loop radiant heat exchanger (model 16-020, 16-050) which includes a built in water filter and deionizer cartridge. Since the anode floats at 15kV, the water must be kept in a constant state of deionization to prevent leakage current. If the leakage current is more than 2 or 3 mA at 15kV of high voltage then the leakage current will start to affect the power regulation on the 32-095 or 32-096 X-ray source control. Normal leakage current (the current that is shown on the HV supply current meter when only the high voltage and no power is applied) should be less than 2mA @ 15kV. Once you get up to 3 to 5mA it is time to replace the water filter and deionizer cartridge.  If the leakage is very high (10mA or more) then it is possible that the heat exchanger flow restrictor is plugged up.

Part of the loop in the cooling flow directs about 10% of the water through the deionizer and filter. There is a flow restrictor just in front of the input to the filter and this flow restrictor can become clogged or corroded over time, resulting in reduced flow to the deionizer cartridge and subsequent increased leakage current.

It is recommended that every time you replace the deionizer cartridge and filter (about once every 3 years is typical) that you inspect the flow restrictor and clean it out if necessary. If it is corroded you may need to drill it out with a tiny drill bit (about .030″).

The pictures below show the location of the flow restrictor and how to remove it for inspection. If it is plugged up then drill it out with a small drill bit and clean it before reinstalling it into the flow restrictor connector

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