RESETTING YOUR TESLAMETER
If you suspect that an error has been experienced by your DTM-151 or 351 serial communication model, resetting the unit to its factory setting will clear this error. But before doing a reset, ensure that your custom user settings are noted. If you are using an automated command script during initial set-up, this will have to be re-run.
To do a reset:
1. There are 2 ways, either by switching S2-8 of your DIP switch found on the serial board under the DTM. Remove the lid and you should see this DIP switches on the board. When turned ON, each power cycle you do will automatically perform a reset on your DTM-151/351 Digital Teslameter and can be seen on the front display. Another way is to use a terminal emulator and send a command CTRL+X. Check that it flashed the "rESEt" message on the front display or on your terminal screen.
DIP SWITCH S2-8 to Reset the DTM
FIXING A "BAD CAL" ERROR
SCOPE:
This procedure applies to all DTM-151-S units with software version 7.0 and above and where the display shows “Bad Cal”.
Note:
This procedure is not applicable if any physical/parts modification was made or the original Analogue board serial number was changed on the DTM unit. Likewise, if unit was subjected to extreme pressure, sparks, or mishandling, unit must be sent back to Group3 for total re-calibration.
STEPS:
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Make the original Calibration Certificate handy. The calibration info is listed on it.
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Attach a working 4-range, Group 3 probe (LPT-141, MPT -141, LPT-231, MPT-231).
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On the DTM serial board, set switches 2 and 3 to ON on DIP switch SW2.
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Attach fibre optic cable to port (if FTR is used) or the RS-232 serial cable connector from the terminal to DTM unit (if RS-232 is used). Refer to pages 3-4 to 3-8 of the user’s manual on how to set up the communication. Additional set-up information provided on pages 3-9 to 3-12.
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Power on the DTM. The terminal emulator should display the DTM model and software version. It also shows that the DTM unit is communicating with the emulator.
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Press “CTRL+X” in succession to “Reset” the unit. (Quotation marks are omitted when typing the commands.)
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Type “*CALIBRATE” to set DTM on calibrate mode.
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Press “D” on keyboard to display the current calibration info of DTM.
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Type “ISB” to inspect error. The emulator should show “Damaged”.
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Type “SSB” to clear the error.
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Type “ISB” again to inspect the chip. It should show “Ok” on the emulator terminal.
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Type “ERASE” to erase the old calibration factors of the unit.
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Type “D” to verify that the calibration factors are erased. See example below.
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Type “Q” to quit calibration. Unit is now ready to accept commands for Manual Input of Calibration factors.
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Follow procedure on “DTM-151Cal Info Manual Encoding (WI-DTM-CAL-002)”.
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Manual Encoding of Calibration Factors
SCOPE:
This procedure applies to all DTM-151-S units with software version 7.0 and above and where calibration info has been corrupted or erased.
Note:
This procedure is not applicable if any physical/parts modification was made or the original Analogue board serial number was changed on the DTM unit. Likewise, if unit was subjected to extreme pressure, sparks, or mishandling, unit must be sent back to Group3 for total re-calibration.
STEPS:
-
Make the original Calibration Certificate handy. The calibration info is listed on it.
-
Attach a working 4-range, Group 3 probe (LPT-141, MPT -141, LPT-231, MPT-231).
-
On the DTM serial board, set switches 2 and 3 to ON on DIP switch SW2.
-
Attach fibre optic cable to port (if FTR is used) or the RS-232 serial cable connector from the terminal to DTM unit (if RS-232 is used). Refer to pages 3-4 to 3-8 of the user’s manual on how to set up the communication. Additional set-up information provided on pages 3-9 to 3-12.
-
Power on the DTM. The terminal emulator should display the DTM model and software version. It also shows that the DTM unit is communicating with the emulator.
-
Press “CTRL+X” in succession to “Reset” the unit. Parentheses are omitted when typing the commands.
-
Type “*CALIBRATE” to set DTM on calibrate mode.
-
Press “D” on keyboard to display the current calibration info of DTM.
-
Type “ERASE” to erase the old calibration factors of the unit.
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Type “D” to verify that the calibration factors are erased. See example below.
Example:
Below is sample calibration info of a corrupted/erased EEPROM chip that would come out on display.
Range 0 Range 1 Range 2 Range 3 Temperature
Mfg Zero (G) 0.000 0.00 0.00 0.00 0.00
Mfg Cal 1.000000 1.000000 1.000000 1.000000 1.000000
Modifying a Mfg Zero Info of a Specific Range
*This is done while still on calibrate mode.
Let’s assume the following calibration factors for R0:
Mfg Zero= 1.653
Mfg Cal= 1.009150
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To manually change the calibration info of Zero reading at Range 0 from 0.000 G to 1.653 G, do the following:
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Type “R0” to select the range. The range indicator LED is shown on the display window.
From the keyboard, type in “SZ1.653” and press ENTER.
Press “D” to show the calibration info and it must show a new value of 1.653 on Range 0.
Range 0 Range 1 Range 2 Range 3 Temperature
Mfg Zero (G) 1.653 0.00 0.00 0.00 0.00
Mfg Cal 1.000000 1.000000 1.000000 1.000000 1.000000
*** Do the same for other ranges.
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Modifying a Mfg Cal Info of a Specific Range
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To change the calibration info of Cal reading of “Range 0” from 1.000000 to 1.009150, do the following:
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Type “R0” to select the range. The range indicator LED is shown on the display window.
From the keyboard, type in “SC1.009150” and press ENTER.
Press “D” to show the calibration info and it must show a new value of 1.009150 on Range 0.
Range 0 Range 1 Range 2 Range 3 Temperature
Mfg Zero (G) 1.653 0.00 0.00 0.00 0.00
Mfg Cal 1.009150 1.000000 1.000000 1.000000 1.000000
*** Do the same steps for other ranges.
Modifying a Mfg Zero Info of Temperature
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*This is done while still on calibrate mode.
Let’s assume the following calibration factors for the Temperature:
Mfg Zero= -2.2
Mfg Cal= 1.022155
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To change the calibration info of Zero reading of “Temperature” from 0.00 to -2.20, do the following:
From the keyboard, type in “STZ-2.20” and press ENTER.
Press “D” to show the calibration info and it must show a new value of -2.20 on Temperature column.
Range 0 Range 1 Range 2 Range 3 Temperature
Mfg Zero (G) 1.653 0.00 0.00 0.00 -2.20
Mfg Cal 1.009150 1.000000 1.000000 1.000000 1.000000
Modifying a Mfg Cal Info of Temperature
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To change the calibration info of Mfg Cal reading of “Temperature” from 1.000000 to 1.022155, do the following:
From the keyboard, type in “STC1.022155” and press ENTER.
Press “D” to show the calibration info and it must show a new value of 1.022155 on Temperature column.
Range 0 Range 1 Range 2 Range 3 Temperature
Mfg Zero (G) 1.653 0.00 0.00 0.00 -2.20
Mfg Cal 1.009150 1.000000 1.000000 1.000000 1.022155
11. To exit calibrate mode, type “Q”.
TESLAMETER GOING OVERRANGE
When a DTM-151 or 351 Digital Teslameter goes overrange, it means that the current field being measured is too high for the selected range. However, if the range selected is already set at the top field (Range 3.0T) and field is expected to be below 3.0T, it could a.) a user set offset is available which adds up to the field measured, b.) the DTM encountered an error which upset the field reading needs a power cycle and a reset, or c.) the calibration data is corrupted. To know if the data is corrupted, user can access the calibration data on calibrate mode (see procedure on "fixing a bad cal error" above).
TESLAMETER READING IS ERRATIC
When a DTM-151 or 351 Digital Teslameter reading goes erratic and jumpy, check if all other ranges is doing the same thing. If only a certain range is jumpy, most likely that the unit has encountered an unexpected error such as probe pins are bent, loose power supply port, or grounding issue. Verify possible cause mentioned above and if problem persist, it may just be a power cycle and a reset that is needed. Jumpy readings especially on just one range may also indicate that the calibration data was corrupted and will have to be re-entered. See above procedure on fixing" bad cal errors" on how to enter the a corrupted data. If all else fails, the unit has to be sent for repairs at our factory in New Zealand.
DTM Display noProbE
When a DTM-151 or 351 Digital Teslameter shows a "noProbE" message on the front display, check first that the probe pins of the plug are all straight and not damaged. If the pins are good, the only other reason for the no probe message is a broken connection of the probe sensor to the main circuitry and this can be either the sensor itself or the wires attached to it. There are times that we can reconnect if the magnet wires are the problem but this will depend or where the cut is. If wires are in good condition without any physical damage, it is highly likely that the hall sensor has suffered a catastrophic failure and has to be sent back for repair to replace the it.
DTM Display Error°C
When a DTM-151 or 351 Digital Teslameter shows an "Error°C" message on the front display, check first that the probe pins of the plug are all straight and not damaged. If the pins are good, the only other reason for the error°C message is a broken connection of the temperature sensor to the main circuitry and this can be either the sensor itself or the wires attached to it. There are times that we can reconnect if the magnet wires are the problem but this will depend or where the cut is. If wires are in good condition without any physical damage, it is highly likely that the temperature sensor has suffered a catastrophic failure and has to be sent back for repair to replace it.