Control Valve Single Acting Positioner Actuators Split Range
C45DF-LSB
TOP-5879F1-C45DF-LSB — Linear Single-Acting Sub-Category (LSA/LSB)
Product Overview
The TORLEO TOP-5879F1-C45DF-LSB is a linear (straight-stroke)
pneumatic smart valve positioner for straight-stroke control
valves, travel 10–150 mm, in a 316 stainless steel housing. Its
feedback lever reads 10–150 mm of straight stroke through a
microprocessor-based non-contact magnetic sensor, giving stable
feedback with no linkage wear. As a single-acting unit it pairs
with a spring-return rotary cylinder and relies on the mechanical
spring to force the valve back to the safe position on loss of air
or power (fail-safe). Flow state: fail-lock (holds the last
position on loss of power or signal; add an air lock-up valve for
strict three-break retention). Enclosure IP66; explosion protection
Ex tb IIIC T85 °C Db; functional safety IEC 61508 SIL 3.
Smart valve positioner, dust explosion-proof Ex tD, straight
stroke, single acting, fail lock, stainless steel
corrosion-resistant, split body anti-high temperature vibration
In the process of production, the control valve is the terminal of
the control system. Once it fails, it will directly affect the safe
operation of the device and have a significant impact on the
production process. Using the intelligent control valve positioner
can improve the flow characteristics and performance of the control
valves. Through digital information, communication with the DCS or
BUS equipment can improve the enterprise’s production control
ability and guarantee the safe and stable production of the device.
Performance indicators
| Item | Indicator |
|---|
| Input signal | 4~20mA or 4~20mA+HART, split-range control can be set |
| Sensor type | flameproof structure rotary |
| Gas source | pressure 1.4~6bar; no oil, no moisture, no dust and dirt |
| Stroke / Travel | 10~150mm |
| Input resistance | 490 Ω (max.) / 20 mA DC |
| Electrical interface | M20*1.5 or customized |
| Pneumatic interface | NPT1/4 |
| Repeatability | ±0.3%F.S. |
| Linear | ±0.3%F.S. |
| Hysteresis | ±0.3%F.S |
| Sensitivity | ±0.2%F.S |
| Output characteristics | linear, quick opening (25:1, 50:1), equal percentage (1:25, 1:50) |
| Protection class | IP66 |
| Explosion-proof grade | Ex tD A20 IP66 T85 °C |
| Security level | SIL3 |
| Fault state | fail lock Off power, off signal, the valve maintains position; add air lock
valve to realize three-break position maintenance |
| Operating temperature | -30℃~85℃ (host), -40℃~110℃ (sensor) |
| Material | 316 stainless steel |
| Gross weight | Main unit 3Kg, sensor 1Kg |
| Dimensions | 162L*152W*182H (mm) |
Technical features of the product
Nozzle baffle + symmetrical membrane valve structure, strong
ability to resist dust, moisture and oil;
Built-in keyboard and large LCD screen, the positioner can be
debugged without a handheld operator;
HART communication, modular design, convenient for users to choose
and use;
Valve position output, modular design, convenient for users to
choose and use;
Configure linear, quick opening, equal percentage and user-defined
flow characteristics;
One-key auto-tuning operation to meet the needs of users for quick
installation and one-touch smart calibration;
PID compound control algorithm can achieve 0.1-0.3% control
accuracy.
Selection guide for TOP-5879F1 C series smart valve positioner
Recommended Applications & Valve Matching
Technical matrix: Linear Single-Acting Sub-Category (LSA/LSB). This unit is a straight-stroke positioner (10–150 mm linear feedback); it couples to globe /
cage-guided linear control valves and must not be fitted to a
quarter-turn ball valve without a mechanical conversion.
- single / double-seated globe control valves (10–150 mm)
- cage-guided sleeve control valves
- pneumatic diaphragm control valves
- high-differential-pressure shut-off service
Fail-Lock Safety & Water-Hammer Protection
On an emergency — loss of power or loss of signal — Fail-Lock logic holds the valve exactly where it was: instead of venting the
actuator, the internal air-lock manifold seals the trapped air
volume in both chambers (OUT1 & OUT2), so the valve neither slams shut nor
drifts. This matters most on long pipelines, where a valve closing
instantly under full flow can generate a violent water hammer (pressure surge) that damages pipework, gaskets and instruments;
by keeping the ball in place until the process is safely
depressurised, fail-lock protects the whole line. Where strict
three-break protection (power / signal / air) is required, an
external air lock-up valve is recommended.
Field Engineering Notes
Our field experience shows that a straight-stroke loop has its own
physics: the thrust must overcome packing friction and, on
spring-return units, the return-spring force. We tune the
proportional gain and integral action to the actuator’s air volume
so the stem neither overshoots nor hunts, and the
microprocessor-based non-contact magnetic feedback sensor removes
linkage wear and signal jump under frequent cycling. PID compound
control keeps accuracy at 0.1–0.3%. Recommended air supply: 1.4–6
bar, oil-free, moisture-free and dust-free.
Why Choose TORLEO
- Straight-stroke control (10–150 mm) — for globe / cage-guided
linear control valves
- Non-contact magnetic feedback — no linkage wear or signal jump
- P-gain + integral action tuned to the actuator air volume — no
overshoot or hunting
- PID compound control keeps control accuracy at 0.1–0.3%
- IEC 61508 SIL 3; Ex tb IIIC T85 °C Db; IP66
Certifications & Compliance
Trust anchors: Functional safety — IEC 61508 SIL 3; Explosion protection — Ex tb IIIC T85 °C Db; Ingress protection — IP66.
IEC 61508 SIL 3Ex tb IIIC T85 °C DbIP66Linear / Straight-StrokeSingle-ActingFail-Lock
