Is your machine downtime costing you money?
You know the feeling. You just fixed the production line, and two days later, the machine stops again. You check the control cabinet, and there it is—the cable is broken inside the drag chain. Or maybe the signal is jumping around, and the servo motor is acting crazy. This is a huge headache for maintenance managers and engineers.Cables in moving parts face a tough life. They get bent, pulled, and rubbed thousands of times a day. If you use a standard cable, it will crack. If you use a cheap cable, electromagnetic interference (EMI) will mess up your data. You need a cable that moves like a snake but protects the power and signal inside. You need the SK-847A-4.
What makes SK-847A-4 special?
This is not just a wire. It is a complete system for movement. We built this cable for one reason: to survive in high-flex environments. The “SK-847A-4” name means it is a specific high-flex design for servo systems.The core of this cable is the conductor. We use fine-stranded bare copper. This is Class 5 flexibility according to VDE standards. Think of it like a rope versus a solid stick. The rope bends easily without breaking. We chose the best stranding pitch (the twist length) to stop the wires from drifting apart when you pull the cable.Inside, you have 4 cores. Each core is 6 square millimeters. That is enough power for most servo motors. But size isn’t everything. The insulation is key. We use high-pressure molded PVC or TPE. This material does not stick to itself. It supports every single strand of wire. This means when the cable bends, the insulation moves with the copper. It does not crack or peel off.
Shielding that actually works
Electrical noise is the enemy of precision. In a factory, you have big motors, VFDs (Variable Frequency Drives), and welders. They all create noise. If your cable is not shielded, this noise gets into your encoder signal. The result? The machine loses position, or the servo drives fault out.The SK-847A-4 has a shield. We use a tinned copper braid. This is a tight mesh of copper wires wrapped around the cores. It catches the noise and sends it to the ground. It protects the data inside.But a shield can be a problem too. If it is too stiff, the cable won’t bend. We solved this. Our shield is made of very fine wires. It is flexible enough to bend with the cable but strong enough to block interference. We also added a drain wire (green-yellow) to make grounding easy for your electrician.
Technical Specifications
Here are the hard numbers for the engineers. You can trust these specs because we test every batch.
- Product Model: SK-847A-4
- Conductor: Fine stranded bare copper (Class 5, IEC 60228)
- Number of Cores: 4 Cores + 1 Ground (Shield)
- Cross Section: 6.0 mm² (approx 10 AWG)
- Insulation Material: Special high-flex PVC / TPE blend
- Sheath Material: PUR (Polyurethane) or Oil-resistant PVC
- Shielding: Tinned copper braid, coverage > 85%
- Rated Voltage: 300/500V (U0/U)
- Test Voltage: 2000V – 4000V AC (1 min)
- Bending Radius:
- Fixed installation: 4 times cable diameter (4D)
- Moving installation: 7.5 to 10 times cable diameter (7.5D – 10D)
- Temperature Range:
- Fixed: -40°C to +80°C
- Moving: -5°C to +70°C
- Flex Life: > 3 to 8 million cycles (depending on bend radius)
- Flame Retardant: IEC 60332-1
- Oil Resistance: Yes (resistant to coolants and lubricants)
- Outer Diameter: Approx 14.5mm (varies slightly by material)
Where to use this cable?
You can use this cable anywhere something moves. But it is specifically designed for servo systems.
CNC Machines and Machining Centers
In a CNC router, the X, Y, and Z axes move fast. The cable carrier (drag chain) moves back and forth all day. The SK-847A-4 handles the constant acceleration and deceleration. It resists the coolant oil splashing on it.
Robotic Arms
Robots need to be precise. If the encoder cable fails, the robot arm crashes. This cable is light and flexible. It does not weigh down the robot wrist. It handles the torsion (twisting) that happens when a robot turns.
Automation Lines and Conveyors
In a factory line, conveyor belts move products. Sensors read barcodes. Servos push parts. All these need power and data. Our cable keeps the line running even if the chain gets misaligned sometimes.
Heavy Duty Hoists and Cranes
For lifting equipment, the cable needs to be tough. The PUR sheath option is great here. It resists abrasion from dust and dirt. It can handle the weight of the cable itself over long vertical runs.
Why choose our SK-847A-4 over others?
You might find cheaper cables on Alibaba or from local distributors. But cheap cables cut corners. They use recycled plastic for fillers. They use solid copper which breaks fast. They skip the shield to save money.Our SK-847A-4 is different.
- Real Copper: We don’t use copper-clad aluminum (CCA). You get pure copper conductivity.
- No “Garbage” Fillers: The center of the cable is a real tension member or properly twisted cores. We don’t fill it with cheap plastic junk that breaks and jams the chain.
- UV and Oil Proof: The outer sheath is tested for hydrolysis and oil resistance. It won’t get sticky or crumble in a hot, oily shop.
- Consistent Quality: We test the insulation resistance. It is over 20 MΩ.km. This means no leakage current.
Installation Tips for Long Life
Even the best cable will fail if installed wrong. Here is how to get the most out of SK-847A-4:
- Don’t pull too hard: Use the tensile center. Pull from the strength member, not the shield.
- Respect the bend radius: Don’t kink the cable. If the bend is too tight, the strands break inside even if it looks okay outside.
- Leave some slack: Let the cable “float” in the chain. Don’t pull it tight like a guitar string. It needs room to move.
- Ground the shield: Connect the green-yellow wire to the ground on both sides (or as per your EMC plan). If you don’t ground it, the shield is just a decoration.
Frequently Asked Questions
Q: Can I use this for underwater ROVs?A: The standard SK-847A-4 is for industrial dry or oily environments. For underwater, we recommend a PE or PUR jacket version with a neutral buoyancy filler. Contact us for the “Waterproof” variant.Q: What is the minimum order quantity (MOQ)?A: We keep stock of common lengths. For custom colors or printing, the MOQ is usually 100 to 200 meters. We can negotiate for larger projects.Q: How fast can you ship?A: For samples, we ship via DHL/FedEx in 3-5 days. For bulk orders (container load), production takes 10-15 days plus shipping time.Q: Is the cable RoHS and CE compliant?A: Yes. We follow ISO 9001, ISO 14001, and REACH regulations. The materials are free of lead, cadmium, and mercury.
Get your custom quote today
Don’t let cable failure stop your production line again. You need a cable that bends, twists, and pulls without giving up. The SK-847A-4 is the heavy-duty solution for your servo motors and automation systems.We are a factory direct supplier. We can customize the length, color, and connector type for you. Whether you need 10 meters for a prototype or 10,000 meters for a new machine line, we can handle it.Click the “Send Inquiry” button now. Tell us your voltage, speed, and bend radius requirements. We will send you a detailed quotation within 24 hours. Let’s fix your cable problems for good.