Yokogawa ProSafeRS vs Istec SpeedSys® 300
In turbomachinery, overspeed protection is critical to preventing failure and ensuring compliance. To help you come to the best decision in choosing the right system, we’ve put out a comparison. In this comparison, we’ll be looking at Yokogawa ProSafeRS and the Istec SpeedSys® 300.
Why forward-thinking OEMs, integrators, and end users choose SpeedSys® 300
Established brands usually work with what’s already there for many years, not taking into account customer feedback and improvement points. Istec however, has built new systems from scratch to fulfill all your current day needs in machine protection and monitoring.
Yokogawa ProSafeRS
Istec SpeedSys 300
Proven-in-use
The Yokogawa ProSafeRS is not certified-by-design, only proven-in-use.
Certified-by-design
The Istec SpeedSys 300® is certified-by-design, its functional safety claims demonstrated through a certified IEC 61508 development and validation process.
System‑integrated protection concept
Standalone protection is not specified as a dedicated function, given the ProSafeRS’ reliance on a full system supporting its overspeed protection.
Standalone protection concept
Each SpeedSys® 300 module performs a complete overspeed protection function independently, clearly separating protection functionality from control and monitoring systems.
Integrated redundancy approach
Redundancy is implemented at system level through rack‑based architecture, dual‑redundant power supplies and configurable cross‑channel voting. Overspeed protection can be implemented using high‑integrity 2oo3 voting configurations within the system.
Modular redundancy approach
Redundancy can be implemented using multiple SpeedSys units, supporting flexible 1oo1, 1oo2, or 2oo3 architectures.
Separate voting and safety outputs
Safety relays and a safety‑related analog output are available directly on the device, reducing external safety hardware.
Integrated safety I/O
Safety relays and a safety‑related analog output are available directly on the device, reducing external safety hardware.
Backplane‑based system design
The Yokogawa ProSafeRS has been built to have a compact size and ability to slot into space-constrained installations.
Compact and practical design
Its compact footprint fits space‑constrained installations and retrofit projects, while maintaining full overspeed protection functionality within a single module.
Communication for diagnostics and integration
The ProSafeRS uses SIS communication software, allowing it to use it separately for diagnostics and monitoring.
Communication for diagnostics
Modbus RTU over RS‑485 is provided for monitoring and diagnostics only and is not part of the safety function.
Centralized installation concept
The focus of the ProSafeRS is not on it being one cohesive overspeed protection system, requiring multiple modules or the backup of a supporting system.
Standalone and distributed installation
SpeedSys® 300 is installed as a standalone device, mounted individually in a control or protection panel. Multiple SpeedSys units can be installed side‑by‑side to implement redundancy concepts, without requiring a shared rack, backplane, or central baseplate.
Lifetime Support
SpeedSys 300 delivers a clean architectural separation between control and trip logic ensuring uncompromised protection compared to integrated systems.
SIL3 by Design
Adapt as needed: from single-channel setups to fully redundant 2oo3 architectures, SpeedSys 300 supports stepwise scalability at every stage.
Compact Footprint and Seamless Integration
Engineered for space-limited panels and demanding environments, it’s ideal for both retrofits and new installations.
FAQ
Yes, it protects against underspeed, overspeed, and acceleration.
Both the SpeedSys 300® and the Yokogawa ProSafeRS are fit for API 670 environments.
Only the SpeedSys 300 supports 2oo3 voting. The Yokogawa ProSafeRS supports 1oo2 and 2oo2 voting.
| Aspect | Yokogawa ProSafe-RS | Istec SpeedSys® 300 |
|---|---|---|
| Key features | SIS for ESD/F&G/BMS applications, dual redundant architecture, Modbus and TCP support | Overspeed, underspeed, and acceleration protection, SIL2/3 capability, safety relays and safety analog output, external voting, Modbus RS-485 |
| Number of relays | Modular I/O output, exact amount of channels is dependent on module type. 30 VDC maximum switching capacity | 2 safety relays (DPST), 2 non-safety relays (SPST), 1 safety 4-20 mA analog output, 1 frequency output. 30 VDC maximum switching capacity. Binary input/output and Modbus RS-485 |
| Frequency range | 100 Hz to 32 kHz | 0.025 Hz to 35 kHz |
| Hardware response time | < 30 ms | < 8 ms |
| Number of inputs ( active) | Unknown, with exact amount of inputs depending on module type | 1 input per module (only one sensor input active at a time) |
| Voting system | Up to 2oo2 included in voting | Up to 2oo3 included in voting |
| Outputs | Exact number of outputs unknown, dependent on module type | • 1 × safety‑rated 4–20 mA analog output • 1 × binary output • 1 × frequency output • Modbus RTU (RS‑485, diagnostics only) |
| Input voltage | 24 VDC | 24 VDC (18 – 36 VDC), dual-redundant power supply |
| Functional safety | Has SIL_capabilities, but is not rated fully as a SIL-capable device | SIL 2 / SIL 3 capable; functional safety embedded in system design |
| Stand-alone protection | Complete overspeed protection, but not independently of a system | Yes – each module performs a complete overspeed protection function independently |
| Relay information | Modular I/O output, rest is dependent on module type | 2 safety relays (DPST), 2 non-safety relays (SPST), 1 safety 4-20 mA analog output, 1 frequency output, up to 30 VDC maximum switching capacity. Binary input/output and Modbus RS-485 |
| Rack / backplane mounting | Not listed | Optional 19‑inch rack for mechanical mounting only; no shared backplane or internal bus |
| Reverse scalability | No reverse scalability listed, which would be with increased difficulty because of necessary system integration | Scalable from single module (SIL 2) to redundant |
Istec ensures the availability and safety of your rotating machinery by providing the most convenient and accessible hardware solutions, delivered by the world’s leading vibration and speed sensing experts.