Application
ScenariosAt a regional wastewater treatment plant in Western Europe, the original S200 control system had been running continuously for more than 22 years. As the plant expanded its aeration basin capacity, operators noticed that several of the older digital output modules were beginning to exhibit sluggish switching — contactor commands arrived late, and the resulting mistiming between blower starters caused periodic 500 A inrush spikes that occasionally tripped the main LV switchboard. The maintenance team sourced original surplus Schiele 2.423.451.00 modules as direct replacements. Because the 2.423.451.00 slots straight into the existing S200 rack backplane without any re-engineering, re-wiring, or software reconfiguration, the swap was completed during a single weekend maintenance window. The new modules’ typical <1 ms on/off switching delay restored crisp, deterministic sequencing; the built-in group isolation (3 kV AC between outputs and bus) eliminated the cross-talk that had previously caused erratic contactor pickup. Six months post-retrofit, the plant recorded zero switchboard trips attributable to output timing, and the electrical supervisor noted: “The Schiele 2.423.451.00 dropped in like it was made yesterday. Our blower staging is tighter than it’s been in two decades.”
Parameter
| Main Parameters | Value/Description |
|---|---|
| Product Model | 2.423.451.00 (also referenced as 2 423 451 00) |
| Manufacturer | Schiele GmbH / Entrelec Schiele |
| Product Category | PMO Transistor Digital Output Module |
| Compatible System | Entrelec Schiele Systron PM S200 / PM S250 PLC & DCS |
| Output Channels | 8 transistor outputs, grouped & electrically isolated (8 points = 1 group) |
| Rated Output Voltage | 20–30 V DC (nominal 24 V DC) |
| Single Channel Current | 1 A continuous |
| Total Module Current | ≤ 4 A |
| Switching Delay | < 1 ms typical (on and off) |
| Isolation Voltage | 3 kV AC between output and bus/power supply |
| Output Protection | Short-circuit current limiting, overload detection, reverse polarity protection |
| Sensor Power Supply | 20–30 V DC, 100 mA, short-circuit protected |
| Bus Power Consumption | ≤ 155 mA @ 26.5–31.6 V DC |
| Bus Fault Behavior | Holds last output state for up to 1 second after bus failure |
| Status Indicators | Green LEDs for power supply normal + per-channel output status |
| Mounting Method | 35 mm standard DIN rail |
| Cooling | Natural convection |
| Operating Temperature | -20 °C to +60 °C |
| Storage Temperature | -40 °C to +85 °C |
| Relative Humidity | 5%–95% RH, non-condensing |
| Vibration Resistance | 5–150 Hz, 0.5 g |
| Shock Resistance | 10 g (11 ms half-sine) |
| Protection Rating | IP20 (cabinet installation) |
| Certifications | VDE, CE |
| Weight | Approx. 0.2 kg |
| Lifecycle Status | Discontinued by OEM — available as original spare / refurbished / surplus |
Technical Principles and Innovative Values
- Innovation Point 1: Grouped Electrical Isolation with 3 kV AC Barrier. The Schiele 2.423.451.00 isolates all eight outputs as a single galvanically separated group from the system backplane and bus logic. This 3 kV AC barrier ensures that a voltage transient on one field device cannot propagate backwards into the controller, protecting the entire S200/S250 rack.
- Innovation Point 2: Intelligent Fault Containment. When a channel experiences a short circuit or overload, the 2.423.451.00 rapidly current-limits and reports the fault via LED and system diagnostics — without sustaining damage or disrupting the other healthy channels in the group. This “fault containment” philosophy keeps the rest of the process running even during a field-wiring incident.
- Innovation Point 3: Sub-Millisecond Switching for Precise Sequencing. With a typical <1 ms on/off delay, the Schiele 2.423.451.00 delivers the rapid response times required for precise actuator sequencing and safety-related shutdowns. In applications such as staged motor starting or interlocked valve manifolds, this speed directly translates into reduced mechanical stress and tighter process control.
- Innovation Point 4: Bus Power-Fail Memory. The 2.423.451.00 can be configured to hold the last known output state for up to one second if communication with the central controller is temporarily lost. This fault-tolerance window prevents unwanted process interruptions during minor network disturbances — a critical advantage in continuous-process industries such as water treatment, power generation, and chemical processing.
- Innovation Point 5: At-a-Glance Visual Diagnostics. Green LEDs on the module face clearly indicate “Supply OK” and the real-time on/off state of each of the 8 output points, allowing technicians to verify logic execution at a glance without laptops or software tools. Combined with the per-channel fault signaling, MTTR (mean time to repair) is reduced from hours to minutes.
