Description
Product Overview
Unexpected temperature rises at medium-voltage switchgear contacts can signal loose connections, oxidation, or increasing contact resistance. The ABB SensyCal FCU400-IR addresses this risk through continuous, contactless infrared temperature monitoring. It processes readings from infrared pyrometers aimed at busbar contact points and circuit breakers, allowing maintenance teams to identify developing hot spots without attaching temperature sensors directly to energized components. In the switchgear monitoring arrangement, the FCU400-IR acts as the measurement and evaluation unit, while the pyrometers provide the temperature readings.
A single FCU400-IR system can monitor up to 12 hot spots, with configurable pre-alarm and main-alarm thresholds. The documented system response time is less than one second, helping operators detect rapid temperature changes. Three digital outputs are specified for pre-alarm, alarm, and device-error signaling; an analog output and MODBUS communication are optional. The unit also supports data logging of temperature values and alarm events, while its local display identifies measuring points and indicates maximum temperatures. An optional Pt100 sensor can measure ambient temperature to provide additional context for interpreting hotspot readings.
For a switchgear monitoring upgrade or legacy replacement, the FCU400-IR should be evaluated as a complete measurement system rather than as an interchangeable temperature controller. Compatibility depends on the installed pyrometers, sensor wiring, selected input configuration, power supply, and output options. ABB documentation identifies a 24 V DC supply, IP40 protection for the measurement computer, and a standard 10-meter sensor cable in the documented configuration. The pyrometer and its mounting arrangement must also suit the target contact points and operating environment. Before commissioning, verify alarm thresholds, sensor alignment, signal scaling, and the control-system response to alarm and device-error outputs.
Product Introduction (Non-Templated)
A loose busbar connection can generate damaging heat before a routine maintenance inspection detects it. The ABB SensyCal FCU400-IR combines infrared pyrometers with a dedicated measurement computer to monitor up to 12 switchgear hot spots without direct contact with energized parts.
With a documented system response time below 1 second, it supports early warning and alarm handling in medium-voltage switchgear. For legacy replacement, verify the existing sensor configuration, 24 V DC supply, and output options before installation.
Key Technical Specifications
| Parameter | Value |
|---|---|
| Product Model | FCU400-IR |
| Manufacturer | ABB |
| Product Family | SensyCal |
| Product Type | Infrared temperature monitoring computer |
| Primary Application | Contactless hotspot monitoring in medium-voltage switchgear |
| Maximum Monitoring Points | 12 pyrometers |
| Ambient Temperature Input | Optional Pt100 sensor |
| Digital Outputs | 3: pre-alarm, alarm, and device error |
| Analog Output | Optional; highest measured pyrometer temperature |
| Communication | M-Bus; optional MODBUS |
| System Response Time | Less than 1 second |
| Temperature Reproducibility | ±0.75% of reading or ±0.75°C, whichever is greater, according to the cited data sheet |
| Pyrometer Optical Resolution | 10:1 for the specified sensor configuration |
| Standard Sensor Cable Length | 10 m |
| Supply Voltage | 24 V DC ±5% |
| Maximum Power Consumption | 10 VA |
| Measurement Computer Protection Rating | IP40 |
| Maximum Ambient Temperature — Computer | 55°C |
| Maximum Ambient Temperature — Pyrometer | 70°C |
| Data Logging | Temperature values and alarm events; up to 200 periods in the documented configuration |
| Display | Backlit graphical display |
| Mounting | Panel or wall mounting, depending on housing configuration |
| Configuration | Depends on ordered sensor-input type and installed options |
| Condition | Unverified; physical inspection and functional testing required |
Specifications are based on ABB SensyCal documentation. Confirm the exact hardware revision, pyrometer model, and installed options before using these values as acceptance criteria.
SENSYCAL FCU400-IR
Related Products
The following items support similar monitoring functions or the surrounding instrumentation system. They are not all direct substitutes for the .
1. FCU400-G — Gas flow computer for corrected gas-volume calculations using compatible flow, pressure, and temperature signals. It serves gas measurement rather than switchgear temperature monitoring.
2. FCU400-P — Process measurement computer used for functions such as signal summation, subtraction, and differential-temperature measurement. Consider it for general process calculations, not infrared hotspot monitoring.
3. FCU400-S — Steam measurement computer for steam flow and related thermal calculations. Its application differs from the ‘s infrared monitoring function.
4. FCU200-W — Measurement computer for water, cooling water, brine, and other supported liquid applications. It is relevant to liquid measurement systems, not energized switchgear monitoring.
5. FCU200-T — Counting and accounting variant for compatible pulse/current conversion tasks. It may fit signal-processing applications where temperature hotspot detection is not required.
6. Sensytherm IR-CS, catalog number 7962997 — Infrared thermometer listed as an accessory for the system. Verify optical range, spectral sensitivity, wiring, and mounting requirements before ordering a replacement sensor.
7. Sensytherm IR accessory, catalog number 7962998 — Listed protective housing accessory for the infrared thermometer arrangement. Check the existing sensor assembly before assuming this part fits the installed hardware.
8. Pt100 resistance temperature sensor — Optional ambient-temperature measurement device. It provides context for temperature evaluation but does not replace the infrared pyrometers used to monitor switchgear contact points.
9. MODBUS communication option — Supports data exchange with compatible supervisory equipment when the required interface is installed. Confirm whether the existing unit has the necessary communication hardware; MODBUS should not be assumed to be standard on every configuration.
Frequently Asked Questions (FAQ)
1. Can the ABB monitor all critical switchgear contact points with one unit?
It can monitor up to 12 hot spots, provided the required pyrometers and compatible input configuration are installed.
For a practical installation, map each measuring point to its sensor and alarm threshold. Larger switchgear lineups may require multiple monitoring systems, depending on the number of points, cabinet layout, sensor distances, and wiring arrangements.
2. Can I replace an existing without replacing the infrared sensors?
Potentially, but compatibility must be established first.
- Identify the installed pyrometer models and their output signals.
- Check the sensor wiring and cable lengths.
- Confirm that the replacement’s input configuration matches the existing sensors.
- Verify alarm outputs, analog scaling, and communication options.
- Test each measurement point after installation.
The input connection type is an important detail: ABB documentation states that the specified Pt100 or transmitter connection configuration cannot simply be changed on-site.
3. Does the support firmware v3.1?
The cited product documentation does not establish confirmed firmware v3.1 compatibility. Do not assume this version is supported without identifying the installed hardware and software revisions.
For a planned upgrade, obtain the applicable manual, software identification, and configuration requirements. Verify communication and alarm behavior on the actual device before placing it back into service.
4. Can I hot-swap the while the switchgear remains energized?
Do not assume that live replacement is permitted.
Although the temperature measurements are contactless, the measurement computer still requires electrical power and connected instrumentation. Removing it may interrupt hotspot monitoring and alarm reporting.
For an operating switchgear installation, establish an approved work procedure, identify any temporary loss of monitoring, and coordinate alternative protection or surveillance with the responsible electrical engineering team. The fact that the sensors do not touch live conductors does not make work on the associated electrical equipment risk-free.
5. How do I verify a new-surplus before installation?
A new-surplus label does not establish factory provenance or working condition.
Use the following checks:
- Match the nameplate, ordering information, and serial number against the purchase records.
- Inspect terminals, enclosure, display, and connectors for damage or signs of previous installation.
- Confirm whether the required pyrometers, cables, and optional interface modules are included.
- Request a functional test report covering temperature inputs, alarm outputs, and communication options.
- Test the assembled system with a suitable temperature reference before connecting it to operational switchgear.
A bare measurement computer should not be represented as a complete monitoring system if the required sensors and accessories are absent.
6. What warranty should I expect when purchasing an replacement?
Warranty terms depend on the supplier’s written agreement and the device’s verified condition. New-surplus stock should not automatically be assumed to carry a full original manufacturer warranty.
Before purchasing, confirm the coverage period, return conditions, functional-failure provisions, and whether testing is included. For critical electrical infrastructure, request written confirmation of the exact model and installed options, along with the test results.
7. Can the send temperature alarms to a PLC or DCS?
Yes, the documented design includes three digital outputs for pre-alarm, alarm, and device error. An analog output and MODBUS communication are optional features.
For PLC or DCS integration, confirm the physical output type, signal assignments, interface hardware, and communication mapping. Test the alarm thresholds and failure indications before relying on the system for operational response.
Procurement note: The ‘s primary application and documented specifications are established, but the supplied unit’s condition, hardware revision, included pyrometers, and installed options remain unverified. Confirm those details before treating it as a complete replacement for an existing switchgear monitoring system.
