Yokogawa 2491-21-10-1-AHD-2-1 Single-function Digital Switchgear Ammeter

Product Description

2491-21-10-1-AHD-2-1 is a single-function digital switchboard meter of Yokogawa POWER SERIES PLUS Model 2491. It is an embedded power meter for switchboards. Suffix AHD denotes the version with analog output and RS485 communication. Built with dedicated DSP metering ASIC chip, it measures AC voltage, AC current, watt, var, power factor, frequency and phase angle. It supports on-site configuration of CT/PT ratio and range, with analog transducer output and Modbus RTU. Metal housing for panel mounting. This model was officially discontinued in March 2017, and is widely stocked spare part for power plant, distribution room and switchgear retrofits.

Specifications

• Model: 2491-21-10-1-AHD-2-1
• Brand: Yokogawa (Japan)
• Series: POWER SERIES PLUS / Model 2491
• Device Type: Single-function digital switchboard power meter
• Measured Parameters: AC voltage, AC current, active power, reactive power, power factor, frequency, phase angle
• Input Code: 21 = 300V voltage input; 10 = base voltage configuration
• Options AHD: 4-20mA analog output + RS485 Modbus RTU
• Communication: RS485 bus, max. 32 meters on one bus
• Mounting: Flush panel cutout mounting, metal enclosure
• Accuracy: High precision industrial metering grade
• Auxiliary Power: Wide-range AC/DC supply
• Rated Frequency: 50 / 60 Hz
• Lifecycle: OEM discontinued (Mar 2017), supplied as new old stock or tested used units

Application

1. Local digital display of electrical parameters for MV/LV switchgears, power distribution rooms and auxiliary cabinets in power plants
2. Monitoring of voltage, current, power and power factor for transformers and feeder circuits
3. 4-20mA analog signal transmission to DCS / PLC for remote acquisition
4. RS485 network connection for centralized monitoring via SCADA
5. Replacement of legacy panel meters, spare stocking and switchgear retrofit projects

Series Models

2491-11-10-1-AHD-2-1, 2491-73, 2491-74, 2491-95, 2490 (multi-function version)