Instrument Troubleshooting
Q1. The filter bag is not sealing
Possible Causes:
The dial on the heat sealer may not be turned up high enough. In order to seal the F57 Filter Bag, the dial must be set at approximately "4" while the XT4 Filter Bag is sealed at a setting of "6." Different lab conditions may effect the proper setting. Experiment with a bag to "dial in" the correct setting.
The heating element is broken. On the sides of the Teflon cover are two shiny metal strips that keep the cover in place. Loosen the screws that keep the strips tight to the base of the heat sealer and remove the Teflon cover. Check to see if there is a break in the heating element. If there is, take the extra heating element from the box that the heat sealer came in and replace the defective element. Additional elements can be ordered from ANKOM Technology.
The Insulator is not properly installed. The insulator should be installed to ensure that the heating element does not touch any of the metal on the base of the heat sealer.
Q2. The agitator is not working
Possible Causes:
Motor wires are loose or disconnected. Unplug the instrument. Inspect the wiring to the motor. Contact ANKOM if a loose or disconnected wire is found.
If wires are intact run this test: Turn the instrument on and press the blue "Agitate" button. Check to see if the motor is turning. (The fan at the bottom of the motor will spin if the motor is turning.)
The Motor Set Screw(s) is too loose. If the motor is turning but the agitator is not, you will need to tighten the set screw(s) on the gray coupler with an Allen wrench. Note: Be sure to unplug the instrument before tightening the set screws.
The Packing Nut is too tight. If the motor is not turning when the "Agitate" button if pressed, you may need to loosen the brass packing nut.
- Unplug the instrument.
- Loosen the brass packing nut so you can turn it easily with your fingers.
- Reach down into the vessel and twist the agitator disk back and forth a couple of times
- Plug the instrument back in.
- Turn the instrument on and press the blue "Agitate" button.
- If the agitation begins, tighten the brass packing nut until you hear the motor begin to labor (you will hear the tone of the motor change slightly. When the tone changes, loosen the brass packing nut 1/8 of a turn and the tone will change back. This is the appropriate tightness.
The agitator may have corrosive buildup. If periodic maintenance was ignored and acid solution was allowed to leak into the packing assembly, the shaft may become "frozen". Check for corrosive buildup. The packing set and agitator may need to be replaced.
The motor may have failed. This is a bit unusual and each of the above possibilities should be investigated thoroughly before ordering a motor. If all of the above steps have been reviewed and the agitator still does not turn, the motor will need to be replaced.
Q3. The controller shows incorrect temperature
To ensure that the controller settings are correct: see Service Procedure #53 (for instruments purchased pre 9/03) or see Service Procedure #44 (for instruments purchased Post-09/03)
If settings are correct you will need to test the controller and calibrate it. To test the controller see Service Procedure #49.
Q4. Bag suspender trays are melted
For illustrations of Melted Trays see Service Procedure #50. Melting of bag suspender trays happen when there is not enough solution in the vessel to cover all of the trays while the instrument's heat is activated.
Possible Causes:
The person operating the instrument did not put enough solution into the vessel to cover all of the trays.
The exhaust valve is slightly open and some of the solution slowly drips out of the vessel during the extraction.
The red heat button is not turned off at the end of the extraction after the solution has been drained from the instrument and the trays are left in the instrument.
There is an adequate amount of solution and the heat is on but the agitation is not turned on.
If bag suspender trays are melted you should do the following:
1). Replace melted trays see links below for:
Complete Bag Suspender
Upper Bag Suspender Trays
Bottom Bag Suspender Tray
2). Inspect inside of vessel to determine if any plastic melted to the walls. If so, fill vessel with water and turn on heat until the water boils. Turn off heat. Carefully scrap the plastic from the walls and remove plastic pieces. Drain water and wipe out any remaining plastic residue.
Q5. The instrument stops heating
When the pressure in the vessel is too high, the pressure switch will turn off the heater.
Possible Causes:
There is too much solution in the vessel. Make sure 2 liters or less of solution is used in the vessel at a time.
The motor is not turning or stalling during a run which will cause a higher temperature in the vessel and thereby raising the pressure. Check to make sure the fan is on the motor. Replace the fan if needed. See Service Procedure #52.
There is a corrosion problem. Inspect the agitator, the bag suspender weight, and the bag suspender rod to see if any corrosion is taking place.
The controller is not calibrated and heater higher than it should. See Service Procedure #49.
The bag suspender is sticking in vessel. See Service Procedure #50.
Analytical/ ResultsTroubleshooting
Q1. What size screen do we use to
grind samples?
Our grinding recommendation for samples to be extracted in our Fiber Analyzer is:
1 mm with a Wiley Mill
2 mm with a Cyclone Mill (such as UDY or Retsch)
Q2. High or Low Assay Results
Check to ensure the procedures sent with your instrument were followed. Some possible variables that may affect your
results are:
General Problems:
- ND chemicals can come out of solution- Heat and stir to bring back into solution
- Oven temperature too hot (102oC-105oC +/-2oC)
- Modifying the settings on the Controller
- Improper weighing technique-See weighing technique in the Appendix of the manual.
- Improper or non-use of the desiccant pouch-A standard desiccator will introduce moisture in the samples as it is being opened and closed. This will cause poor precision.
Low Values:
- Grind is too fine
- Bag is not completely sealed
- Broken seam in bag allowing sample to escape from bag
- Digestion run too long (ADF & Crude Fiber)
High Values:
- The movement of the bag suspender is less than 1/2" (1.2 cm) up and down.
- Solution is not heated sufficiently-Perform ANKOM Boil Test (see Service Procedure #49)
- ND- Failure to use Alpha Amylase and/or Sodium Sulfite
- AD/ND-Sample too high (>5%) in fat and not pre-treated with solvent
- Crude Fiber-always pre-soak with acetone
- Oven temp low, wet samples introduced next to dry samples-samples are not sufficiently dried.
- Lack of or incorrect use of desicant pouch-check for holes in pouch, packets not dried regularly-refresh desiccant
- Rinse water not hot enough (70°C+ ND,AD) (50°C +CF) or not long enough (5 minutes)
- Digestion not run long enough
- Acetone re-used for removing water from bags
post extraction
- Improper calculation of blank bag correction or using the wrong values in the formula
- Bag sealed too low
- Too much sample in the bag
- Vessel lid was not closed tightly enough (The tightness of the lid only applies to the A200,A200I,A220)
Q3. Why should I use MoistureStop Desiccant Pouches?
Many instruments in the marketplace have the capacity to run 6 samples at a time. After being dried, the beakers, flasks or crucibles are placed into a counter top or cabinet desiccator. Once cooled, they are then removed one at a time and weighed. Each time the desiccator is opened to remove a sample, moist ambient air is introduced inside the desiccator. However, because the lid or door of the desiccator is opened just 6 times, the samples that remain in the desiccator after each item is removed are affected very little by ambient moisture that may be introduced.
With Filter Bag Technology, generally larger numbers of filter bags are extracted at a time. As with the beakers, flasks, and crucibles mentioned above, if the bags are placed in a desiccator after drying, each time the lid or door is opened to remove a bag, moist ambient air is introduced. Because the desiccator is opened up to 24 times, the moisture can more readily affect the remaining bags. If a collapsible, ANKOM desiccant pouch is utilized, the air can be pushed out of the pouch each time a filter bag is removed. This technique provides an accurate and precise result. Every month it is possible to place the small desiccant packets into the oven at 100-105°C for a few hours to insure that the desiccant is renewed. In addition, to insure the integrity of the desiccant pouch, regular replacement of the zip lock bag should
be considered.
Q4. Can I do sequential analysis using FBT?
It is possible, and may be desireable, to follow an NDF with an ADF using the same sample and filter bag. The only draw back is that some samples will produce a lower than expected ADF value when an NDF is run first. The reason for this is that certain components like pectin, tannins, glucans and fructans are removed by NDF solution but not by ADF solution. Therefore, these components are not present in the sample when the ADF follows the NDF. As mentioned above, when you test these types of samples, you will have artifically lower ADF values than you would if you had only run an ADF without the NDF. This issue, of course, has nothing to do with the filter bags. They will hold up to both assays with no problem. In fact, you can even follow the ADF with a lignin procedure using the same bags if you wish.
Q5. Why is my blank bag heavier after the run than before the run?
Our grinding recommendations for samples to be extracted in our Fiber Analyzer is:
1mm with a Wiley Mill
2mm with a Cyclone Mill (UDY, for example)
If samples are ground any more finely, there will be sample loss from the F57 Filter Bag during the extraction and lower than expected fiber values will occur. Obviously, this sample loss happens to a greater extent with products that tend to grind more finely than others.
Generally, the best way to determine if sample has been lost is to examine the blank bag values. If the blank bag multiplier is greater than 1 (blank bag is heavier after the run than it was before), then fine particles have definitely escaped from the filter bags (with samples in them) during the extraction process. Some of these particles have been deposited upon all the filter bags in the vessel (including the blanks) and have created blank bags that are heavier after the process
than before.
Q6. Can the ANKOM Filter Bags be ashed?
The F57 filter bags is ash free and therefore can be used for ash determination. See Service Procedure #29 for the
Ashing procedure.
Q7. What are the required temperatures for the hot water rinses?
It is important that the rinse water going into the instrument be at least 50°C for Crude Fiber and 70°C for detergent fibers. For safety purposes, most hot water heaters are set lower than 70°C. In addition, if there is a substantial distance between the instrument and the hot water heater, the rinse water will, at least initially, be even cooler. For these reasons we suggest the purchase of a small hot water heater that can be placed next to the instrument. ANKOM Technology has a small (10 liter) Water Heater suitable for both the A2000/2000I and the A200/A200I available for purchase.
Q8. Should I use distilled water in my
fiber rinses?
Rinse water can come directly from the tap. It does not have to be distilled.
Q9. How do I determine Blank Bag Correction Factor?
The Blank Bag Correction allows for a weight adjustment based on actions that take place during solublization. The resulting factor adjusts your sample bag weight in an up or downward direction. To determine Blank Bag Correction, you simply include at least one empty, sealed and weighed filter bag (blank bag) with your run. After the samples and blank bag have been through the solubilization process and dried as required, you simply divide the end weight of the blank bag by the start weight. This will result in a factor usually in the 0.992-0.998 range. The Blank Bag Correction can also be used to calibrate your values to a known value.
Q10. What is the porosity of the ANKOM F57
Filter Bags?
The porosity of the ANKOM F57 Filter Bag 25 microns +/- 15. The design of the filter bag provides a 3 dimensional filter matrix similar to the filtering effect of a glass crucible. The F57 Filter Bag provides equal filtration without the manual intervention required with a crucible method.