Is it possible to connect 6 two-wire RTDs to ADS124S08 Analog to Digital Convert

[ashmit_jaiswal]

I have connected 6 two wire RTDs to a ADS124S08 Analog to Digital Converter in series and parallel connection. My requiernments are to connect as many RTDs as possible to the chip with least amount of extra equipment and to achieve a mix between accuracy and number of RTDs.

The attached image is a schematic of 6 Two Wire RTDs connected to a ADS124S08 Analog to Digital Converter. I would like to know the following things about my idea:

1) Will the AINCOM pin acting ac IDAC1 be complying with the load of 6 RTDs? [Both]
2) Will there be any division of current across the 3 sets of 2 RTDs and if yes, then will it affect the functionality of the RTDs [Parallel connection]
2) Will there be any distorting in the readings of the RTDs? If yes, then till what extent and will it be filterable by any hardware or software?
3) Is there any chance of any unexpected error which I have not predicted yet?
4) Is there any other way/schematic to achieve this objective?
5) which of the two methods is better?

[zapta]

Your software will need to derive the resistance of each of the 6 RTDs. I suggest to assign actual numbers (e.g. PT100 vs PT1000, resistor values, IDAC currents, etc) and:

1. Write the formulas for the 6 resistances.

2. Verify that you are within the working range of the ADS124S0x  (e.g. the input voltages that you get on the ADC and reference inputs).

3. Compute the expected worst case resolution (ideal ADC steps / Ohm, at the worst temperature points).

The second design is more intuitive because the resistance formulas are independent for each channel (#1 above). 

[Salitronic]

Unless I am missing something, you have an underdetermined system, you cannot calculate the individual RTD resistances by this system.
You only know the total current going through the 3x2 RTD array and the voltage across each RTD.
The current in each parallel branch will be different, so you have 9 unknowns (6 resistances and 3 currents) and not enough equations to calculate it.

[ashmit_jaiswal]

so in the schematic where the RTDs are connected in series can we calculate the resistance of each RTD using the reference current or is there another method to do that. Also please tell me what errors we can expect.