Description
Reviews
| Brand | - |
| Category | Electronics & Electrical / PLC |
| Origin | - |
| Model Series | SR40, SR20, SR30, ST40, ST30, ST20 |
| Compatibility | Siemens S7-200 SMART Architecture |
| Input Voltage | AC 85-264V or DC 24V (Model Dependent) |
| Digital Inputs | 12 to 24 points depending on model |
| Digital Outputs | Relay or Transistor (Source/Sink) |
| Communication Ports | Integrated RS485 and Ethernet (PROFINET) |
| Programming Software | Compatible with STEP 7-Micro/WIN SMART |
| Mounting Type | Standard DIN Rail 35mm |
| Operating Temperature | -10°C to +55°C |
| Warranty Period | 12 Months Manufacturer Warranty |
Anonymous
Mar 29, 2026
Rating: 5/5
Fast shipping and good packaging
Ordered ten SR20 units for a client project. They arrived well-packaged and programmed easily. The terminal blocks are sturdy and easy to wire.
Anonymous
Mar 25, 2026
Rating: 5/5
Reliable and robust
Been running the SR30 in a dusty workshop environment for six months without a single glitch. The relay outputs handle our solenoid valves effortlessly.
Anonymous
Mar 25, 2026
Rating: 4/5
Solid performance for the price
These controllers offer about 80% of the premium brand features at half the cost. For non-critical applications, this is the smartest economic choice available.
Anonymous
Mar 25, 2026
Rating: 4/5
Great value for small automation projects
The ST20 model works perfectly for our packaging machine. Setup was quick using the standard software. Only giving 4 stars because the manual could be more detailed in English.
Anonymous
Mar 12, 2026
Rating: 5/5
Excellent communication features
The built-in Ethernet port on the ST40 makes HMI integration incredibly fast. We connected it to our SCADA system in under an hour. Highly recommended for modernizing plants.
Anonymous
Mar 11, 2026
Rating: 5/5
Perfect replacement for legacy systems
We used these SR40 units to upgrade an old production line. The compatibility with existing Siemens code was seamless, and the price point made it feasible to replace all controllers at once.
Q: Is there a battery required to retain the program?
A: No, these SMART PLCs utilize non-volatile memory (EEPROM) to retain your program and data permanently without the need for a backup battery.
Q: Can I use the original Siemens STEP 7-Micro/WIN SMART software to program these?
A: Yes, these PLCs are fully compatible with the standard STEP 7-Micro/WIN SMART programming environment, allowing you to use existing projects with minimal changes.
Q: Does the SR40 model support analog expansion modules?
A: Yes, the SR40 supports various analog expansion modules for temperature, voltage, and current signals, expanding its I/O capabilities significantly.
Q: Can I connect multiple PLCs via RS485 for Modbus communication?
A: Absolutely. The integrated RS485 port supports Modbus RTU protocol, allowing you to network multiple units as masters or slaves easily.
Q: What is the difference between the SR and ST series?
A: The 'SR' series features Relay outputs suitable for switching AC or DC loads, while the 'ST' series uses Transistor outputs designed for high-speed DC switching and pulse generation.
Antique-Style Ceramic Brush Washer, Large Glazed Water Pot for Calligraphy and Painting, Complete Set with Brush Holder
$21.20
Black Rutilated Quartz and Crackle Quartz Loose Beads for DIY Crystal Jewelry
$0.58
Data Cable Organizer, Charging Cable Manager, Desktop/Wall Circuit Wire Clips, Self-Adhesive Sorting and Fixing Holder
$3.80
Beijing Dental Implants - Implant with Abutment at Bulk Procurement Price (Korea Dentium & USA Brands) by Hezhong Dental
$100.00
Universal Bamboo Joint Fume Extraction Arm Welding Smoke Exhaust Pipe Industrial Waste Gas Collection Hood Support-Free Suction Arm
$33.30
Fengzhu Wet-Dry Separation Waterproof Bag Shoulder Crossbody Pack for Outdoor Fitness Swimming Camping Electronics Storage
$109.00
Palette for Traditional Chinese Painting, Oil, Acrylic - Art Student and Kids Painting Watercolor Pigment Tray
$5.78
Huirui Polypropylene (PP) Super Glue - Fast-Setting Adhesive for Metal, Plastic, TPE, Silicone, Soft PVC, and TPU
$16.80
Bybo Dental Sweden Nobel CC Dental Implant Package Including Crown and Abutment
$6,924.00
Remote Control Negative Ion Air Purifier Home Indoor Formaldehyde Smoke Odor Haze Removal Intelligent Sterilization Disinfection Machine
$76.30
Car Tire Stone Removal Hook, Tool for Clearing Stones Stuck in Tires to Prevent Blowouts, Multi-Function Stone Extractor
$8.42
Motorcycle and E-bike Storage Hook Kit - Multi-function Hanging Hooks for Storage Boxes, Locks, and Racks
$2.01
Mojo 100% Cotton Baohong Watercolor Line Art - Beginner Watercolor, Colored Pencil & Marker Coloring Kit: Cat Letters
$32.80
![[X11] McDull Little Theater Series Plush Sticker Blind Bag, Official Authentic Trendy Collectible Hanging Ornament Toy](https://www.gosteppe.com/cache/small/product/269614/legacy-main-c0c30a047a8b8fb01f07e4d1.webp)
[X11] McDull Little Theater Series Plush Sticker Blind Bag, Official Authentic Trendy Collectible Hanging Ornament Toy
$41.60
Factory Supply Food Processing Equipment - High-Yield Fruit Pitting Machine for Commercial Berry Peeling and Mud Removal
$6,210.00
Fast Shipping Stone Removal Hook New Car Tire Stone Cleaner Tool Multi-Function Vehicle Stone Remover
$29.82
Five Elements Balance Keychain – Pixiu Charm with Natural Crystal Pendant for Wood/Fire Enhancement
$42.40
Chunfei Grocery Store: Commuter Hard Fork Low-Top Tube Mountain Bike for Urban Roads, Suburbs, School Runs, and Outings
$2,246.00
Infant Rattle Toy - Baby Soothing Shaker Drum for Newborns, Chewable and Safe for Boys and Girls
$10.90
Car Tires for Sedans and Vans, Original Equipment Sizes 165/175/185/195/205R in 14/15/16 Inches
$59.00
New Cute Tomato-Shaped Cable Organizer Clip for Charging Cords and Headphone Wires, Fabric Fixed Winding Management
$15.60
Yokohama 245/50R19 V107E 105W Original BMW iX3 EV Tire - Factory Removed
$382.00
DC Drive Equipment
$18,800.00
Meiyike Plant Slow-Release Fertilizer – All-Purpose Nutrient Pellets for Green Plants and Flowers, Household Controlled-Release Compound Fertilizer
$20.15
Pelican Air 1535 Waterproof Shockproof Lightweight Case - Photography Equipment Safe with Wheels - 1535TP Carry-On
$2,565.00
Exclusive for 618 Live Stream 20260508
$199.00
Compact Home Range Hood, Portable USB Desktop Smoke Extractor for Living Room Hot Pot and BBQ Odor Removal
$41.00
Seed Bead Tassel Song Brocade Accessories DIY Ancient Style Bracelet Bag Chest Ornament High-Quality Pendant Versatile Tassel Accessory
$2.98
Popular Pagoda-Shaped Tea Set - Chinese Style Kung Fu Tea Ceremony Set for Home, Living Room, and Office Guest Reception
$67.00
Swiss-Type Lathe External Thread Insert 60° CNC TKFT12RA60005 Stainless Steel Cutting Tool RN6001
$33.00
![[Dangdang Machinery] German Imported Helukabel 4x2x0.25+2x1 Integrated Power and Network Cable 8+2](https://www.gosteppe.com/cache/medium/product/437884/legacy-main-19e2e1d822bc48ad489f93f5.webp)
