DataMate MP Q&A

DataMate MP Links: Datasheet   Manual

Question: I want to read a dc voltage using manual mode and the bare wire adaptor. What are the proper connections?

Answer: The proper connection depends on the version of firmware that you have. Press the status button (a clock) to find the version number. The version is actually a date: mm.dd.yy.

Start manual mode (press the check mark) and then choose an appropriate voltage range. Then:

If your firmware is version 05/01/02AA or newer, connect wires as follows:

• Terminal 5: +VDC
• Terminal 7:  -VDC
• Terminal 10: Shield

Question: I want to read Gage Technique embedment strain gauges. Do you have a sensor definition for them?

Answer: Yes, we do. Click the link below to download an mdb file that contains the definition for both Hz and uStrain readings. The definition uses sweep A instead of Auto. This is important to minimize hunting when successive sweeps are out of phase with the wire oscillation, since the sustain time is longer than the reading rate. For best results, we recommend taking more than one reading and either average the readings or toss out high and low readings.

How do I set the DataMate MP to read zero when there is no load on my load cell?

Answer: Use the MP Manager program to set up the sensor definition and determine the engineering units to be used. Take an initial reading with no load. This reading will be used as the “Datum” in the “Datum Reading tab” in MP Manager. Enter the value as expressed in desired engineering units. Check the box to subrtract this datum from following readings. Leave “Offset” and “Sensitivity” as %FS, as noted on the cal sheet.

The “Offset” is defined in units of %FS and is divided by “Sensitivity” after being subtracted from the reading. On the other hand, “Datum” is subtracted from the calculated result without further modification. Consequently, the “Sensitivity” and “Offset” are normally entered directly from calibration sheet while “Datum” is used to zero the no-load reading.

The no-load reading is usuallyslightly different from zero because the calibration uses a best fit method.

Question: How can I read a Keller PSI piezometer with the DataMate MP?

Answer: The DataMate MP manual shows wiring. Here is a sensor definition file called keller-piezo.mdb . There are instructions below that tell how to copy the definition from one database to another.

Question: How can I read a PT100 RTD with the DataMate MP?

Answer: We've set up a sensor definition file called pt100-mdb that should help you. Wiring is shown below. You can transfer any of these sensors to your own database (To do this, see "how can I transfer a custom sensor" below).

The first two sensor definitions use 2-wire connections, but you'll probably want to use the third sensor definition called 3wRes. It uses all three wires from the PT100. Here is a wiring diagram.

1. Connect wire 1 from the PT100 to bare-wire-adaptor terminals 1 and 5.
2. Connect wire 2 from the PT100 to bare-wire-adaptor terminals 2 and 3.
3. Connect wire 3 from the PT100 to bare-wire-adaptor terminals 4 and 7.
4. When you press the record button, the DataMate MP stores two readings, Resistance 1 (the resistance of the sensor + resistance of the lead) and Resistance 2 (the resistance of the lead only.)
5. Enter these readings into a spreadsheet and subtract Resistance 2 from Resistance 1.

Question: I want to read a Geokon vw piezometer, but the MP Manager software doesn't seem to configure the sensor properly. What can I do?

Solution 1: Obtain a reading in Hz2/1000: Choose Piezometer - VW, then enter 0.001 for the A factor, 0 for the B factor, and 0 for the C factor. For temperature, choose thermistor.

Solution 2: Obtain a reading in engineering units: You will need the Linear Gage Factor (G) and the Regression Zero (R0) from Geokon's calibration sheet.

1. Choose Piezometer - VW.
2. For the A coefficient, enter -0.001 x G.
3. For the B coefficient, enter 0.
4. For the C coefficient, enter (G x R0).
5. This will give you a reading in the units of G (typically psi). If you want to have a different unit, multiply the A and C values above by a conversion factor. For example to convert from PSI to meters head of water, multiply A and C by 0.0703089 and enter these new values for A and C.
6. For temperature, choose thermistor.

Question: Can I use the DataMate MP to read 4-20 mA sensors? Can I use the MP datamate in this situation? Do I need a separate 12 volt DC supply to get the system powered up? Are there risks associated with this approach?

Answer: The MP offers two ways to read 4-20 mA sensors. The two schemes are in the MP manual on page A-8. If you choose the 4-20mA method, you must disconnect any power supply. In this case, the MP powers the sensor and supplies the termination resistor.

If the sensors are powered already and you cannot disconnect the power, then you can read with the 1-5Vdc method. In this case, you bring out two wires from the loop, a + voltage wire and - voltage wire. Connect a 250 ohm resistor between the two wires, then insert the +V wire into terminal 5 on the Mp's bare wire adapter and the -V wire to terminal 6. Just two wires should be connected. (The manual shows terminals 8 and 9 also, but that is incorrect. )

To create the sensor in the MP Manager program, select either Generic Current or Generic Voltage and work from there to enter calibration factors, etc. So long as you follow the power source guidelines above, there should be no risks.

Question: I have custom sensors in one database. I want to move them to another database. How can I do this?

Answer: The MP Manager program does not have a specific command for moving custom sensors from one database to another, but there is a fairly easy way to accomplish this.

1. Open the database that contains your custom sensor. Choose Edit Sensor List. Select the custom sensor and click the Edit button. When you do this, MP Manager automatically copies the sensor information into its own clipboard. Now, click cancel and close the sensor list. Don't close MP Manager.

2. Open your other database. (You want to copy the custom sensor into this database). Choose Edit Sensor List. Click Add. For sensor type, scroll to the bottom of the drop down list and choose customer. Click the Next button. The sensor dialog appears. All the information on the MP Manager's clip board has been copied into the custom sensor field. Now you simply enter a name for the sensor and click Save.

3. If you have another custom sensor to copy, repeat the two steps above.

Question: How do I use the DataMate MP to read EL-SC sensors?

Answer: The DataMate MP provides two ways to read sensors: manual mode, which emulates manual readouts, and program mode, in which you use a sensor definition created by the MP Manager program.

• For manual mode readings, choose EL SC RO. (Requires firmware version 05/01/02AA or later).
• For program mode readings, you must define a "custom" sensor. We've made this a bit easier by providing a sensor definition that you can download. Download the EL SC sensor definition. The file is called elsc25.zip. After downloading, unzip it, then open the resulting elsc25.mdb file with MP Manager (Do not use Access). The file provides definitions for the A, B, and T channels of a single sensor. Duplicate these definitions for additional sensors, using an unique identifier for each sensor. The sensor definitions provide a reading in volts. You can enter coefficients listed on the calibration record to convert the volts readings to engineering units.
• Connect the sensor cable to the bare-wire-adapter as shown in the table below.

Question: I have some older EL SC sensors with a 250 mV SC board. How do I read them with the DataMate MP?

Answer: The DataMate MP provides a manual mode and a program mode for reading sensors, as explained in the answer above.

• For manual mode readings, choose EL SC RO. (Requires firmware version earlier than 05/01/02AA).
• For program mode readings, you must define a "custom" sensor. We've made this a bit easier by providing a sensor definition that you can download. Download the EL SC sensor definition. After you download the file, unzip it. Then open the resulting file, called elsc250-mdb. It holds five definitions below: ELSC1 is a uniaxial sensor that gives a reading in volts. Use it for EL SC beam sensors or EL SC tiltmeters that were shipped before Nov 2002. This sensor does not include a temperature channel. ELSCT is used to read the thermistor only. It can be used with ELSC1 above. EL250A, EL250B, EL250T are used to read a biaxial sensor (reading in volts) with temperature in Degrees C. The three names will appear as one name in your DataMate MP list of sensors. Use these definitions for EL IPI and EL MonoPod sensors that were shipped before Nov 2001. If you have more than one sensor, make a copy for each sensor, giving it a unique name.
• Connect the sensor cable to the bare-wire-adapter as shown in the tables below. )

Question: What kind of memory is used in the DataMate MP?

Answer: The DMMP has three 128K x8 bit Low Power CMOS Static RAM chips, manufactured by Samsung. Two of these chips (256 kB) are used for data storage.

Question: I can't establish communication with the DataMate MP. What's wrong?

Answer: Have you installed a "hot link" program for synchronizing your palm top computer? Right-click on its icon and choose exit. If you can now communicate, the hot link program is causing interference and you must exit it before you use the MP Manager program.

Question: I can't open my database with MP Graph. What's wrong?

Answer: We underestimated the number of sensors that users might add to their database. In your case, you had over 100 sensors. The new limit is 500 sensors. Please go to the following link to download the newest version of MP Graph.

http://www.slopeindicator.com/downloads/software-windows.html

Question: MP Graph gives me error 50003 when I try to open a database. What's wrong?

Answer: To make the MP Graph setup file smaller, we excluded some files that we thought your computer had already. The workaround is to download and install the VW MiniLogger Manager. Then try MP Graph again. It should work now (as of 7/24/2002).

Question: Can I edit data with MP Graph?

Answer: Yes. We've added this feature to the latest version of MPGraph (see link above). Here's how to put MP Graph into edit mode:

1. Load the database.
2. Click the close button or the x. This takes you to back to the start screen.
3. Choose View - Full Data Table. The data table appears. Maximize the screen so you can see the entire table. Data values are ar the far right.
4. Right click on the data table and choose Edit.
5. You can sort the data by clicking on the column labels. For example, to sort the table by ascending values, click the Value label.
6. To delete a reading, highlight the entire row by clicking on the gray square at the left of the row. Then press the delete key.
7. When you are done editing, close the database to make your edits take effect.
8. Then reopen the database to make your graphs.

Question: The DataMate MP displays -------- for the VW sensors and 276 deg C for the temperature sensor. What's wrong?

Answer: You probably have a bad connection to the sensor. Disconnect the sensor. Does the reading stay the same? Look for a broken wire or a bad soldered joint.