Product Overview: The Emerson A6125 Upgrade Solution
When replacing older seismic sensors with modern piezoelectric types, the Emerson A6125 two-channel piezoelectric vibration monitor delivers a reliable upgrade path. Designed for high reliability in critical rotating machinery such as steam turbines, gas compressors, and hydro turbo machines, this 1-slot plugin module reduces cabinet space by half compared to traditional four-channel 6U cards. The Emerson A6125 is API 670 compliant, hot-swappable, and features remote selectable limit multiply and trip bypass, making it an ideal choice for upgrading your CSI 6500 Machinery Health Monitor system.
Technical Specifications
| Parameter |
Value |
| Number of Inputs |
Two, independent, differential |
| Type of Inputs |
Piezoelectric (accelerometer or velometer) |
| Input Resistance |
>100 kΩ |
| Signal Input Voltage Range |
-5 to +15 VDC (6125/00: 311-9500 mV p-p; 6125/10: 16-450 mV p-p) |
| Frequency Range (Accelerometer) |
High: 30-8000 Hz; Med: 10-2000 Hz; Low: 6-1000 Hz |
| Sensor Supply |
Accelerometer, constant current, 2-8 mA, 30 VDC |
| Power Consumption |
Max 6 W, 250 mA at 24 VDC |
| Operating Temperature |
0° to 65°C (32° to 149°F) |
| Dimensions |
100 x 160 mm (3.937 x 6.300 in), 30 mm width (6 TE), 128.4 mm height |
| Weight (net) |
Approximately 320 g (0.705 lbs) |
Real-World Applications
The Emerson A6125 excels in monitoring case vibration from accelerometer sensors on rolling element bearing machines and gearboxes. In nuclear power plant applications, case measurements with piezoelectric sensors are standard, and this module provides accurate alarm setpoints with configurable alert and danger delays. For upgrading existing systems, the monitor supports both RMS and zero-to-peak measurement modes across three filter frequency ranges, ensuring compatibility with legacy installations.
Installation and Setup Guidance
The Emerson A6125 occupies one slot in a 19-inch rack, with dimensions sized for a 3U chassis. It is hot-swappable, allowing replacement without powering down the system. Connect piezoelectric accelerometers or velometers using the differential inputs; ensure the sensor supply voltage does not exceed 30 VDC. Front panel LED indicators provide channel OK, alert, and danger status. Use the Mini DIN RS-232 configuration socket for parameter setup and monitoring.
Compatibility and System Integration
This module integrates seamlessly into the CSI 6500 platform and supports PlantWeb and AMS Suite. It offers ModBus TCP/IP output for analysis parameters (½x, 1-10x, phase angle) and includes rear buffered outputs (0-10 VDC) and 0/4-20 mA current outputs for each channel. The Emerson A6125 works with Ovation and DeltaV process control systems, providing integrated machinery health data.
Selection Guide and Purchasing Advice
Before purchasing, verify your sensor type: the Emerson A6125 supports accelerometers and velometers with piezoelectric output. Choose the variant (6125/00 or 6125/10) based on your sensor’s voltage range. For relay expansion, consider the A6740 relay card for extended alarm delays (0-36 seconds). At UBEST Automation (ubest101), we stock genuine Emerson CSI parts. Contact our team for compatible accessories and application support.