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Error on 3-wire measure with the EVAL-AD7124-8SDZ

Category: Software
Product Number: AD7124-8

I have an AD7128-8 conected to a 3-wire measure circuit to read from a PT1000. I am following the steps of the RTD Configurator and error budget calculator. 

My problem is that the measure i'm getting is:

Digital sample: 6919806.000000
RTD: 552.944214
Digital sample: 6919790.000000
RTD: 552.942932
Digital sample: 6919734.000000
RTD: 552.938477
Digital sample: 6919654.000000
RTD: 552.932068
Digital sample: 6919639.000000
RTD: 552.930908

When i should be getting around 1110 ohms

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The steps i'm following on the code to measure the RTD are: 

//1. Setting the 50uA [AIN0+ (IOUT0) / AIN1- (IOUT1)]

ad7124_regs[AD7124_IOCon1].value =0x910;

//2. Analog input [AIN2+ / AIN3-]

ad7124_regs[AD7124_Channel_0].value =0x8043;

 

//3. Configuring the PGA to 16, the unipolar mode, and the external references [REFIN1+ / REFIN1-]

ad7124_regs[AD7124_Config_0].value =0x1E4;

//4. Writing of the registers

ad7124_write_register(ad7124_handler, ad7124_regs[AD7124_IOCon1]);

ad7124_write_register(ad7124_handler, ad7124_regs[AD7124_Channel_0]);

ad7124_write_register(ad7124_handler, ad7124_regs[AD7124_Config_0]);

//5. Waiting for conversion

ad7124_wait_for_conv_ready(ad7124_handler, timeout);

//Rref= 21500ohms 1%, on the polimeter it reads 21460ohms

ad7124_read_data(ad7124_handler, &sample);

RTD =(sample * 21460)/(16*pow(2.0, 24)); //UNIPOLAR

printf("RTD: %f \n", RTD);

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This are the schematics:

I am working at the moment with the EVAL-AD7124-8SDZ, and these are the conexions on the plaque.