Implementing 3-Switch XOR Ladder Logic with Internal Bit
Implement a 3-SPST switch XOR light circuit in LogixPro or RSLogix 500 using an internal relay bit. Includes truth tables, boolean equations, and verified.
Operating as the primary sequence control and networking engine within high-demand automation systems, the Mitsubishi Electric R08ENCPU delivers high-speed instruction execution combined with native network integration. Designed for the MELSEC iQ-R Series platform, this CPU module features built-in dual RJ45 ports that support CC-Link IE Controller Network, CC-Link IE Field Network, and standard Ethernet communications directly on the processor card. With an execution speed of 0.98 nanoseconds for basic LD instructions, the module minimizes system cycle times while managing sophisticated control algorithms and high-bandwidth fieldbus data simultaneously.
| Parameter | Specification Value |
|---|---|
| Manufacturer | Mitsubishi Electric |
| Model Number | R08ENCPU |
| Control Series | MELSEC iQ-R Series |
| Program Capacity | 80K steps |
| LD Instruction Execution Speed | 0.98 ns |
| Local I/O Points | 4096 points |
| Internal Current Consumption (5 V DC) | 1.49 A |
| Communication Interfaces | CC-Link IE Control, CC-Link IE Field, Ethernet (RJ45 x 2), USB 2.0 (Mini-B) |
| Operating Temperature Range | 0 to 55 degC |
| Dimensions (W x H x D) | 56 mm x 106 mm x 110 mm |
| Net Weight | 0.40 kg |
| Interface Port | Connector Type | Functional Role |
|---|---|---|
| P1 (Port 1) | RJ45 | CC-Link IE Field / Control / Standard Ethernet connection |
| P2 (Port 2) | RJ45 | CC-Link IE Field / Control / Standard Ethernet daisy-chain/ring port |
| USB Connection | Mini-B USB | Direct local programming, diagnostics, and parameter configuration |
| SD Memory Slot | SD / SDHC Card Slot | Data logging, firmware updates, and offline backup storage |
The R08ENCPU represents a double-width module on the iQ-R base unit due to its integrated network hardware. If replacing a standard R08CPU, ensure that you have configured sufficient base unit slot allocation, as the R08ENCPU consumes two physical physical slot locations (though it registers under a single logical slot). When upgrading legacy Q Series systems (e.g., Q06UDVCPU or Q13UDVCPU), program conversion can be performed via GX Works3. However, communication instructions must be refactored to utilize the newer iQ-R system labels and protocol structures.
A major parameter to calculate is the internal power consumption. At 1.49 A on the 5 V DC internal bus, this CPU places a significant load on the backplane. When pairing this module with multiple high-current analog modules or additional motion CPUs, verify that the total current draw does not exceed the maximum output of the system power supply module (such as the R61P which provides 5.0 A). If the rating is exceeded, split the configuration across extension base units or upgrade to a higher-capacity power module.
To prevent electromagnetic interference from disrupting CC-Link IE communications, double-shielded twisted pair (STP) Category 5e or higher cables must be used. Ensure that the cable shielding is continuously grounded through the RJ45 metallic shell to the main chassis ground of the iQ-R rack. Additionally, if configuring a ring topology on the network, enable the loopback function within the GX Works3 network parameters; otherwise, an accidental break in the ring may cause a communication timeout instead of self-healing.
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Operating as the primary sequence control and networking engine within high-demand automation systems, the Mitsubishi Electric R08ENCPU delivers high-speed instruction execution combined with native network integration. Designed for the MELSEC iQ-R Series platform, this CPU module features built-in dual RJ45 ports that support CC-Link IE Controller Network, CC-Link IE Field Network, and standard Ethernet communications directly on the processor card. With an execution speed of 0.98 nanoseconds for basic LD instructions, the module minimizes system cycle times while managing sophisticated control algorithms and high-bandwidth fieldbus data simultaneously.
| Parameter | Specification Value |
|---|---|
| Manufacturer | Mitsubishi Electric |
| Model Number | R08ENCPU |
| Control Series | MELSEC iQ-R Series |
| Program Capacity | 80K steps |
| LD Instruction Execution Speed | 0.98 ns |
| Local I/O Points | 4096 points |
| Internal Current Consumption (5 V DC) | 1.49 A |
| Communication Interfaces | CC-Link IE Control, CC-Link IE Field, Ethernet (RJ45 x 2), USB 2.0 (Mini-B) |
| Operating Temperature Range | 0 to 55 degC |
| Dimensions (W x H x D) | 56 mm x 106 mm x 110 mm |
| Net Weight | 0.40 kg |
| Interface Port | Connector Type | Functional Role |
|---|---|---|
| P1 (Port 1) | RJ45 | CC-Link IE Field / Control / Standard Ethernet connection |
| P2 (Port 2) | RJ45 | CC-Link IE Field / Control / Standard Ethernet daisy-chain/ring port |
| USB Connection | Mini-B USB | Direct local programming, diagnostics, and parameter configuration |
| SD Memory Slot | SD / SDHC Card Slot | Data logging, firmware updates, and offline backup storage |
The R08ENCPU represents a double-width module on the iQ-R base unit due to its integrated network hardware. If replacing a standard R08CPU, ensure that you have configured sufficient base unit slot allocation, as the R08ENCPU consumes two physical physical slot locations (though it registers under a single logical slot). When upgrading legacy Q Series systems (e.g., Q06UDVCPU or Q13UDVCPU), program conversion can be performed via GX Works3. However, communication instructions must be refactored to utilize the newer iQ-R system labels and protocol structures.
A major parameter to calculate is the internal power consumption. At 1.49 A on the 5 V DC internal bus, this CPU places a significant load on the backplane. When pairing this module with multiple high-current analog modules or additional motion CPUs, verify that the total current draw does not exceed the maximum output of the system power supply module (such as the R61P which provides 5.0 A). If the rating is exceeded, split the configuration across extension base units or upgrade to a higher-capacity power module.
To prevent electromagnetic interference from disrupting CC-Link IE communications, double-shielded twisted pair (STP) Category 5e or higher cables must be used. Ensure that the cable shielding is continuously grounded through the RJ45 metallic shell to the main chassis ground of the iQ-R rack. Additionally, if configuring a ring topology on the network, enable the loopback function within the GX Works3 network parameters; otherwise, an accidental break in the ring may cause a communication timeout instead of self-healing.
Global Express Shipping
Returns & Warranty
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| Country of origin |
United States
|