SIEMIENS SIMATIC 505 Analog I/O Module

Conversion formula:

Voltage input (± 10V range): Digital quantity (WX)=(input voltage/10V) × 32000;

Current input (0-20mA range): Digital quantity (WX)=(input current/20mA) × 32000.

3.2 Analog Output Module (PPX: 505-6208A/6208B)

3.2.1 Working principle

The module receives a 16 bit digital signal from the controller and converts it into a continuous analog signal through digital to analog conversion (DAC) technology. The voltage and current outputs are synchronized (the same channel can output two types of signals simultaneously without switching):

The current output is designed as a source type, and in the event of a short circuit, the current will bypass the on-site equipment. It is necessary to avoid short circuits in the output circuit;

If the digital sign bit (bit 1) is 1 (negative value), the module does not update the output and maintains the previous positive value output.

3.2.2 Key Technical Parameters

Parameter category PPX: 505-6208A PPX: 505-6208B

Number of channels: 8 channels, single ended output: 8 channels, single ended output:

Signal range voltage: 0-10VDC; Current: 0-20mA (source type) same as left

Resolution 12 bits (voltage: 2.5mV/step; Current: 5 μ A/step) Same as left

Conversion accuracy (25 ℃) Voltage: ± 0.5% of full scale; Current: ± 0.5% full range same as left

Full temperature range precision voltage: ± 1.45% of full range; Current: ± 1.83% full range same as left

Temperature coefficient voltage: 136ppm/℃; Current: 204ppm/℃ Voltage: 50ppm/℃; Current: 100ppm/℃

Response characteristic response time: 27ms (minimum) -54ms (maximum); Stability time: Voltage 0.2ms, Current 2.0ms Response time: Maximum 10ms Stability time: Same as left

Load requirement voltage: ≥ 5000 Ω, maximum capacitance 0.01 μ F; Current: 10-600 Ω (over 600 Ω requires 10V power supply, maximum 1000 Ω) Same as left

Power demand base power supply: maximum 2W (typical 1.0W); User Power Supply: 20-28VDC, 0.5A (Ripple ≤± 0.4VDC, UL Class 2) Same as Left

3.2.3 Digital Format and Signal Conversion

The controller outputs a 16 bit digital quantity: bits 1-12 are valid data, bits 13-16 are invalid bits (fixed to 0);

Conversion formula:

Voltage output: Digital quantity (WY)=(target voltage/10V) × 32000;

Current output: Digital quantity (WY)=(target current/20mA) × 32000.

Installation and wiring specifications

4.1 Wiring Core Requirements

4.1.1 Cable selection and protection

Cable specifications: 14-24 AWG (0.18-1.5mm ²) shielded twisted pair, supporting stranded (multi strand) or solid (single strand) wires;

Temperature and voltage resistance: The wire has a temperature resistance of ≥ 75 ℃ and a rated voltage of ≥ 300V, meeting the insulation requirements of industrial environments;

Anti interference measures:

Separate the wiring of signal cables and power cables (such as motor power lines) to avoid parallel laying, and form a 90 ° angle when crossing;

Avoid laying cables on vibrating surfaces, do not bend them into sharp angles, and use cable trays for standardized routing;

Shielding layer grounding: The shielding layer of the input cable is grounded at the signal source end, and the shielding layer of the output cable is grounded at the controller base end. It is strictly prohibited to ground both ends at the same time (to prevent noise caused by ground circulation).

4.1.2 Output module circuit calculation

Current circuit resistance: circuit cable equipment (L is the cable length, cable is the unit length resistance, equipment is the on-site equipment resistance); When the circuit is between 10-600 Ω, connect it directly; When the circuit is between 600-1000 Ω, a 10V DC power supply needs to be connected in series in the circuit; When the circuit is greater than 1000 Ω, it is necessary to replace the thick wire diameter cable or shorten the wiring distance, otherwise the output accuracy will decrease.

Fixed error of voltage circuit: The error equipment cables must ensure that the error is within the allowable range.

4.2 Terminal block wiring

4.2.1 Terminal block types and wiring steps

Terminal block model:

Standard configuration: PPX: 2587705-8006;

Optional: PPX: 2587705-8002 (wiring method consistent with standard, can replace old terminal blocks of double width modules);

Wiring steps:

Strip wire 0.25 inches (1.0cm), optional installation of fork/ring terminal blocks (Amp 321462/327891, compatible with # 4 studs);

Connect the wires according to the pin diagram (Figure 2-4), first connect the D terminal, then connect the C, B, and A terminals in sequence, and tighten the screws to ensure good contact;

After the wiring is completed, check the terminal definition to avoid misconnection (such as the "Return" terminal of the input module cannot be suspended, and the "24V common" output module needs to be reliably grounded).

4.2.2 Input module wiring differences

Key points to note for input type wiring method

Voltage input (± 5V/± 10V) signal+connected to voltage input terminal (such as channel 1 connected to A2 "V1 in"), signal - connected to return terminal (A3 "Return 1") does not need to be short circuited, ensuring that the internal resistance of the signal source is ≤ 1k Ω to avoid signal attenuation