Precision Measurement Engineering, Inc.
Precision Measurement Engineering, Inc.
SCAMP has points where customers sometimes have difficulties. Here is an incomplete list!
SCAMP'S SHIPPING BOX
SCAMP will survive only 10g accelerations. The box, foam pads, and popcorn are designed to protect SCAMP from a drop onto concrete from a 5 foot elevation. PME has shipped SCAMP in this box for 10 years with good results. Do not discard the box when you receive SCAMP. Retain it and use it to store and ship SCAMP. Do not make your own protective case, especially do not use plastic cases with foam inserts.
SCAMP's RETRIEVAL LINE
SCAMP's retrieval line is constructed of Spectra, 500 pound test. You cannot break it under tension. However Spectra can be cut and can be melted by excess heat. When using SCAMP insure that the line will not come against any sharp points anywhere on the boat or other places. Inspect the retrieval line from time to time for frays, especially at the point shown by the pencil in the picture above. If you make repairs to the line and use heat shrink tubing, be very careful not to melt the line when shrinking the tubing.
SCAMP's 9V BATTERIES
SCAMP's 9V batteries implement the + and - analog power. These batteries rest against SCAMP's digital card (the bottom of which is visible when the batteries are removed).
Be absolutely certain that you plug the batteries properly onto the connectors. Do not even momentarily touch them in reverse position to the connectors. The batteries will not plug on this way, but they will attempt to power the analog circuits with reverse polarity. No permanent damage, but you will have to replace the analog fuses located in the wiring to the connectors. Fuses are the small yellow cylinders shown in the picture above.
Do not press the batteries deeply into the chassis. This places pressure on the digital card and can cause the connector from the digital card to the analog card to become partially unplugged. No permanent damage, but SCAMP will fail the analog test. If this happens, then squeeze the analog and digital cards back together to re-connect the connector. Lithium 9V batteries are somewhat larger than alkaline and are especially prone to this problem.
Remove these batteries if SCAMP will not be used for long periods.
SCAMP's AA BATTERIES
SCAMP's AA batteries implement the digital power. Note that there are 6 batteries required and that they are placed into the pack with different orientations. There is a legend within the battery pack that shows the orientation. Be sure you use all 6 batteries and that they are placed into the battery pack properly.
These batteries are heavy and are held in position by spring contacts. If SCAMP is accelerated axially, then the batteries will press against the spring contacts and may break electrical contact. Axial accelerations may cause SCAMP to behave erratically.
SCAMP consumes about 1 mA from this pack during periods of in-activity. This limits the endurance of this pack if SCAMP is shelved for days.
Remove these batteries if SCAMP will not be used for a long period.
Lithium AA batteries work fine in this battery pack.
SCAMP's BUBBLE TEST
SCAMP's bubble test adaptor (shown above on a SCAMP with a PAR I/O connector, but similar on standard SCAMPs) screws into 10-32 threads that are tapped into the plastic end cap. These threads are exposed when the bubble test port screw is removed. This screw is shown in the picture above. These plastic threads are easily stripped.
There are three points where the threads may be stripped. The first is when tightening the bubble test port screw. This screw should be tightened finger-tight. Tighten enough to completely compress the o-ring and bring the screw head into contact with the end cap. Then tighten an additional 1/8 turn.
The second point where the threads can be stripped is when screwing the bubble test adaptor into the end cap. If the squeeze bulb (not shown in picture above) and tube are connected to the adaptor, then it is very difficult to get the adaptor properly started in the threads. Disconnect the tube from the adaptor prior to starting it into the threads. Install the tube after the adaptor is fully screwed into place. The tube needs only be pressed gently and partially onto the adaptor.
The third point is when the adaptor is unscrewed from the end cap. If the squeeze bulb and tube are connected to the adaptor, then they tend to bend it sideways at the last threads and will tear them out. Remove the bulb and tube before unscrewing.
SCAMP's I/O CONNECTOR
SCAMP's I/O connector implements connection from SCAMP to the host computer USB port. The picture above shows this connector for the PAR cable, but a similar bulkhead connector is used on a non-PAR SCAMP.
The contacts within this connector are powered and are not water resistant. Always cover this connector with the supplied rubber cover prior to placing SCAMP into the water. When connecting to your computer, carefully dry the connector after removing the cover and prior to plugging the connecting cable.
Never twist the connecting cable. Plug it straight on and pull it straight off.
If you loose the rubber cover PME has supplied a spare in the items shipped with SCAMP.
A few drops of silicone oil on the rubber from time to time will make plugging/unplugging go more easily.
SCAMP's PAR I/O CONNECTOR
SCAMP uses a special connector when a PAR sensor is installed. The connector is shown in the picture above with the cable coupled.
The circuits within this connection are very sensitive to water. Carefully dry this connection prior to disconnecting. Be sure this connector is connected either to the connecting cable or to a dummy connector when placing SCAMP into water, for example when performing the bubble test.
The connecting cable is very fragile at the point where it joins to the metal connector. There is a re-enforcement placed at this point. This is the larger diameter black cylinder just next to the titanium colored metal. Bending of this cylinder, or nearby this cylinder, will cause breaks in the internal wiring of the cable. SCAMP will become unable to connect to the host computer via USB. Be sure to never bend the cable in this region. The most likely time that the cable will be bent is when SCAMP is fully assembled and rested upon its bottom end - where the cable connects to SCAMP. The following picture shows the connection.
PME provides a protective cylinder that slips over the cable and connector. It will keep the connection straight in the event that SCAMP is accidentally rested upon the lower end. This cylinder is secured with a small cable tie pointed by the pencil in the picture.
SCAMP's PAR I/O CABLE
SCAMP's PAR I/O cable connects from SCAMP to the PAR sensor and also to the USB I/O connector. There is a 'Y' near the middle of this cable.
The 'Y' is not very strong and does not resist bending very well. Do not bend the cable in this region. When installing this cable onto SCAMP's drag plate insure that this region is not bent. Proper installation can be seen in the previous section picture above.
SCAMP's FLUOROMETER ELBOW
SCAMP's fluorometer uses two elbows to route water through the fluorometer, one of which is shown above. Water is routed through a clear tube within the end cap. This tube is sealed at each end with an o-ring. There is no retainer provided to hold this tube in its proper location. If the tube is pressed inwards from either end, then it will release the o-ring seal and water will enter SCAMP. The fluorometer elbows each have a white sleeve the prevents the elbow from being screwed too far into the end cap and pressing upon the glass tube. However the elbow can be screwed in too far by excessive force. Only screw the elbow in to the point where the white sleeve touches the end cap. If the elbow is not in the proper orientation, then do not screw it in further. Instead, unscrew it until the proper orientation is obtained.
The glass tube end should be 0.250" in from each side of the fluorometer.
SCAMP's INTERNAL WIRING HARNESS
SCAMP's internal wiring harness (flat amber ribbon in picture above) is very fragile and is easily damaged. Most damage occurs after sharp bending of the harness nearby any of the connectors. If the harness must be disconnected from a connector, do not pull on the amber ribbon. Instead gently pry the connector apart with a sharp blade or pull the connector apart with small pliers by grasping the connector posts visable above the ribbon.