Sharp 5030i User manual

Sharp 5030i/5014i - Cleaning the Filter Assembly
Occasionally the filter assembly needs to be taken apart and cleaned. Gaps in the PM10 inlet screen
can allow insects and debris to get trapped in the filter chamber. Wood smoke can cause sticky
deposits to build up on the top plate. This can lead to the filter tearing or jamming.
When dismantling the filter assembly, great care needs to be taken so that the detector and its
protective film are not damaged. The following is a step-by-step procedure for cleaning the filter
assembly.
1. Turn off the instrument and unplug the power. Disconnect the heater.
2. Remove the Nephelometer (5030i only) by undoing the electrical cable, loosening the two
side screws and then lifting straight up.
3. Remove the 2-part lid, first the small filter assembly cover, then the larger lid. Set them aside.
4. Remove the two 4mm bolts holding the inlet tube in place. Slide off the green clamping
brackets and the inlet adapter. Cut the tape close to the plastic guide and then loosen the
brass knurled nut on the take-up spool and slide off the tape. See Photo 1.
Photo 1 – Remove inlet support bracket and tape

5. Remove the the knurled nut, aluminum discs, blue o-rings and back plate. See Photo 2.
Photo 2 – Remove take-up spool
6. Remove the detector cable from the amplifier. Remove the two 4mm bolts holding the detector
in place. Gently lift up the detector and slide the cable through the hole. If there is a yellow
temperature sensor cable going through the hole, cut the Tyrap that holds it in place and
remove it first. Lay the detector on a flat service to protect it. Be careful of the Mylar Film below
the detector. See Photo 3.
Photo 3 – Removing the Detector

7. To remove the top plate, first remove the two 2.5 mm screws and then remove the four 4mm
screws – alternating one turn at a time. Holding the inlet tube, lift off the top plate. If the middle
plate starts to lift also, hold it with one hand as you wiggle off the top plate. See Photo 4.
Photo 4 – Removing the Top Plate
8. Once the top plate is removed, cut the filter tape near the right roller and discard the short
section with the dirty spots. The design of the 5030i has the dirty tape scrape across the
plastic guide (left side of Photo 4) and travel upside down across the top plate. With a damp
cloth (alcohol is best), clean the guide and the top of the plate. Slide off the black insulation
covering the inlet tube, then remove the two 7/64 allen screws. Remove the inlet tube, being
careful of the o-ring. Wad up a damp piece of paper towel so it fits snugly into the inlet tube
and then push it through with a piece of ¼inch Teflon tubing. Repeat if necessary. See Photo
5.
9. Turn the top plate over and clean the dirty spots off the bottom of the plate. Pinch the head of
a Q-tip with your fingers and use it to clean around the centre hole – being very careful not to
insert it far enough to touch the mylar film – Photo 6. Also use a Q-tip to clean inside the hole
where the inlet tube was connected.

Photo 5 – Remove Inlet Tube and Clean Top of Plate
Photo 6 – Clean Bottom of Plate

10. The Middle Plate is usually fairly clean but give it a quick check. Look through the hole and
see if there is any dirt on the Radiation Source. Generally, it is not advised to lift this plate off
the “Donut” o-ring – it could cause a leak. If there is dirt that can’t be lightly blown off the
Source, then try inserting a wet corner of a tissue (such as a Kim Wipe) between the two bars
and gently drag it across the surface of the Source. Drag the dry end of the tissue across the
Source to absorb the excess moisture. Alternatively, try to gently lift the plate. If there is
resistance, then put the plate back down. If it lifts easily, then remove the plate to gain access
to cleaning the Source. Make sure you put the plate back the same way it came off, making
sure the 4 springs fit into the 4 holes. Clean any debris off the alignment pins. See Photo 7.
Photo 7 – Middle Plate and Source

11. Re-assemble in the following order:
- Make sure the middle plate is in place.
- Pull the filter tape over the right roller, across the middle plate and up through the plastic
guides. Ensure there is enough excess to reach the take-up spool in a later step.
- Attach the inlet tube back onto the top plate (don’t forget the o-ring). Slide the insulation
back over the tube – make sure the “flat spot” is at the bottom so it doesn’t scrape on the tape.
- Holding the inlet tube, gently drop the top plate onto the middle plate, making sure the
alignment pins slide into the two holes.
- Make sure the 4 spacers are in place over top of the 4 screw holes.
- With one hand push down on the top plate, then insert the four 4mm bolts with the other
hand.
- While still holding down the plate, tighten the 4 bolts snugly, but not tight.
- Insert the two 2.5mm screws and snug them up.
- Tighten the four 4mm bolts, then tighten the two 2.5mm screws.
- Re-insert the detector and tighten the two 4mm bolts. Insert the cable through the hole and
connect it to the amplifier. If there was a temperature sensor that was removed, feed it through
the hole and secure it in place.
- Re-install the take-up spool hardware – see Photo 2 above.
- Remove the plastic liner from the old tape roll and put it back on the take-up spool. Tape the
filter onto it, rotate the liner to snug up the tape, then tighten the knurled nut.
- Put a tiny bit of grease on the o-rings of the inlet adapter (threaded heater connection for the
5014i and straight nephelometer connector for the 5030i) and slide it onto the inlet tube.
- Slide on the green clamping brackets and tighten the two 4mm bolts.
- Install the large section of the lid. Leave off the small section of the lid for now, so the tape
advance can be verified.
- For the 5030i, slide on the Nephelometer, tighten the two screws and the electrical
connector.
- Power up the analyzer and verify that the tape advances.
- Let it warm up for half an hour, then do a flow calibration and leak check.