5800 Refrigerated Sampler Service Guide - Isco

5800 Refrigerated Sampler
Service Guide
Section 2 Sample Delivery System
2.1 Pump To produce accurate and repeatable samples, the pump uses a
pump revolution counter and patented 1 non-contacting liquid
detector. The 5800 uses a peristaltic pump housed in a separate,
easily serviceable and fully replaceable module.
CAUTION
This sampler has a high performance pump. As with all such
pumps, it relies upon liquid to cool working components. If the
sampler is programmed to pump in the absence of liquid in
excess of 5 minutes, excessive heat buildup may damage the
paddles, rollers, and housing. Ensure that the liquid inlet is
completely immersed.
Liquid Present .75V
Functional testing and
diags
Test points
For functional CPU board testing through Hyper Terminal, see
Section 4.3.3 Functional Tests. The tests are listed by category in
Table 4-2.
Refer to Section 5.1.5 for standard 5800 pump diagnostics.
For a complete list of 5800 test points and values, refer to
Section 4.2. Test points are also highlighted in red on the CPU
schematic in Figure A-4, Appendix A.
Test Point 5, located on pin 5 of U4-A on the CPU, gives the filtered
AC signal from the liquid detector.
Test Point 1 is the liquid detector rectified A to D signal, or the
input to CR2. When liquid is present, this value should be
greater than 0.75V, as shown at left.
No Liquid Present 0V
1. United States patent 5,125,801
2-1