To get this fault, the temperature sensor in one or more of the paddle heaters is reporting low temperatures. This could occur at different times under specific conditions.
- During paddle pre-heat if any one of the paddles does not reach 50°C in 5 minutes.
- During the Amylase phase if any one of the paddle sensors does not reach 90°C in 25 minutes. Also applies to Trizma phase in the AOAC2009.01/2011.25 methods.
- During the AMG or Protease phase if any of the paddle sensors fail to maintain at least 45°C (temperature range is 60°C +10/-15°C). Also applies to Protease phase during AOAC2009.01/2011.25 methods.
Below is a list of potential causes of the E5 fault:
- Bag breakage: Confirm that an IDF or Flow-thru bag did not break during one of the heating periods. If a bag were to leak near Clamp Bar B and if fluids were to get on one of the paddles, the liquid evaporation will drop the paddle temperature and possibly cause this fault. If this has occurred, the instrument is sensing a real drop in temperature at the wetted paddle and no repair to the instrument is needed. Clean the area from the leaked bag. Test results from a broken bag should be disregarded.
- Greater volume in the IDF or Flow-thru bags: Confirm that the volume calibration is accurate. Rerun the volume calibration as described in the operator's manual (QC/Calibration Checks section). If, for example, the volume calibration is significantly off, there could be an average of 50mls of buffer delivered instead of the required 40mls. This would create a delay in reaching temperature.
- Pre-heat of paddles has been by-passed: In Diagnostics there is the option under Service Mode to "Bypass Amylase Phase Initial Heat-up." If this has been inadvertently pressed (stating "YES") this will bypass the paddle preheat to 50°C and take longer to heat up once the Buffer/Amylase is added. Make sure this option says "NO." This feature is typically used only for demo purposes.
- Clamp Bar A is left open: If for any reason Clamp Bar A was left open during the Amylase phase heat up, there will be more evaporative cooling which will require more time to heat the bags. NOTE: normally Clamp Bar A will close automatically after the final delivery to the IDF positions, but it can be re-opened.
- Front cover left open or localized draft: Be sure to use the front safety cover, especially during the Amylase phase. If this cover is left open, and/or if there is a nearby A/C vent creating a draft toward the front of the instrument the Amylase phase heat-up will take longer. Also, if the TDF instrument is located inside a hood, turn off the air flow to the hood during the Amylase phase heat-up. The continued upward airflow will create a significant delay in reaching temperature. Addressing these may resolve the problem.
- Alcohol - Buffer containers connected incorrectly: Ensure that the containers are connected correctly to the color-coded supply lines on the right side of the instrument. Confirm that alcohol did not inadvertently get put in the buffer container, and that buffer was not put in the alcohol containers. If either of these things happen, and alcohol gets dispensed to the IDF bags at the start of the Amylase phase, the alcohol will boil at a much lower temperature and not reach the target temperature of 97°C.
If the suspect paddle heater takes significantly longer to heat than the others or fails to heat up, there is a problem with either the heater within the Paddle Bar Assembly or with the I/O2 circuit board. If the Paddles heat to the touch but one of the sensors shows an erroneous low reading, there is a problem with the sensor, and the Paddle Bar will need to be replaced or with the newer style Paddle Bar Assembly the individual paddles (TDF48) can be replaced (Contact ANKOM to verify which paddle assembly you have).
For further assistance, contact ANKOM Technology at https://www.ankom.com/contact/technical-services or 1-315-986-8090. Follow TDF Service Procedure #TS021 for replacement instructions of the Paddle Bar assembly (TDF23).
If one of the paddles fails to heat normally, and to rule out a problem with the I/O-2 circuit board, remove the back and top panel of the Electrical Enclosure so that the I/O-2 circuit board can be seen. Do not touch wiring. Perform this simple test:
1. In Diagnostics, select Heater Test.
2. Select Paddle Heater Power Enable.
3. Check that LED #2 lights on the I/O-2 board in the electrical enclosure.
4. Leaving the above enabled, select Paddle #1, and inspect the LED (refer to chart below for each LED).
5. Repeat for each paddle heater. The following is a list of the paddles and the corresponding LED #:
- Paddle Heater Power Enable - LED 2
- Paddle 1 - LED 15
- Paddle 2 - LED 12
- Paddle 3 - LED 9
- Paddle 4 - LED 7
- Paddle 5 - LED 4
- Paddle 6 - LED 1
To test the power coming from the power supply to the individual paddle heater you will need a voltmeter set to DC. Connect the red lead on the voltmeter to the #20 position on the 24-volt DIN rail. Now turn all the heaters on and test voltage as follows. On the back of the I/O2 circuit board are two 10-pin connectors labeled CN-3 and CN-4. To test the power to each paddle, touch the black lead of the voltmeter to the following contact.
- Paddle 1 - CN4, #2 position (wire label 53)
- Paddle 2 - CN4, #5 position (wire label 50)
- Paddle 3 - CN4, #8 position (wire label 47)
- Paddle 4 - CN3, #2 position (wire label 45)
- Paddle 5 - CN3, #5 position (wire label 42)
- Paddle 6 - CN3, #8 position (wire label 39)
You should detect 25.0 volts +/- 0.2 volts at each circuit. If voltage is low there may a problem with the power supply or voltage adjustment. For details on replacing TDF110 Power Supply B see Service Procedure #TS032 Power Supply B Replacement (TDF110).
If all the LEDs are lighting up as normal and voltage is normal, the problem is with a paddle heater within the Paddle Bar Assembly. Follow Service Procedure #TS021 for replacement instructions of the Paddle Bar assembly (TDF23) or with the newer style Paddle Bar Assembly the individual paddles (TDF48) can be replaced (Contact ANKOM to verify which paddle assembly you have).
For further assistance, contact ANKOM Technology at https://www.ankom.com/contact/technical-services or 1-315-986-8090.