ACE949-2

Configured for 2-wire Modbus RTU communication in Sepam protection relay systems, the Schneider Electric ACE949-2 (ACE949-2 RS485 interface module) provides a physical RS485 interface between Sepam Series 20, 40, 60, and 80 devices and an engineering or supervisory local area network.

Hardware Specifications

Parameter	Specification
Model	ACE949-2
Brand	Schneider Electric
Product Type	RS485 Interface Module
Supported Systems	Sepam Series 20, 40, 48, 60, 80, 80 NPP
Communication Protocol	Modbus RTU
Communication Interface	RS485, 2-wire
Network Interfaces	E-LAN and S-LAN
Rated Supply Voltage	12 VDC +/- 10%; 24 VDC +/- 10%
Maximum Supply Current	16 mA receiving; 40 mA maximum sending
Local Signalling	LED for link activity
Mounting	Fixed, symmetrical DIN rail
Dimensions	88 mm H x 72 mm W x 30 mm D
Weight	0.1 kg
Operating Temp	-25 to 70 deg C
Maximum Cable Distance	Up to 1000 m for 5 devices at 24 VDC
Earthing Terminal	Screw-type connector; 2.5 to 50 mm2 cable or 6 to 100 mm2 tinned copper braid
Earthing Terminal Torque	2.2 N.m
EMC	IEC 60255, IEC 61000, ANSI C37.90 series
Voltage Interruption Immunity	100% interruption during 100 ms, IEC 60255-11
Mechanical Standards	IEC 60255-21-1, IEC 60255-21-2, IEC 60255-21-3
Climatic Operating Range	-25 to 70 deg C

Schneider Electric RS485 and Modbus Communication

The ACE949-2 provides a 2-wire RS485 physical interface for Modbus RTU communication. The interface can operate through the E-LAN or S-LAN network interface of compatible Sepam systems. Power is supplied directly by the Sepam device.

The specified network distance varies with device count and supply voltage. At 24 VDC, the source data specifies distances of less than 1000 m for 5 devices, less than 750 m for 10 devices, less than 450 m for 20 devices, and less than 375 m for 25 devices.

The interface includes front-panel LED indication for link activity. The earthing connection uses a dedicated screw terminal with a specified tightening torque of 2.2 N.m.

Frequently Asked Questions

Q: What communication protocol does the ACE949-2 support?
A: It provides a 2-wire RS485 physical interface for Modbus RTU communication through the E-LAN or S-LAN interface.

Q: What supply voltage does the module use?
A: The ACE949-2 accepts 12 VDC or 24 VDC, each with a +/- 10% tolerance, with power supplied directly by the Sepam device.

Q: How is the ACE949-2 mounted?
A: The module is designed for fixed mounting on a symmetrical DIN rail.

Field Installation Guidelines

Mount the ACE949-2 on the specified symmetrical DIN rail and maintain mechanical clearance for the front LED and wiring terminals. Connect the RS485 conductors according to the Sepam communication wiring arrangement and maintain appropriate separation from high-voltage and high-current conductors.

Connect the dedicated earthing terminal using the specified conductor or tinned copper braid arrangement. Apply the specified 2.2 N.m tightening torque. For RS485 wiring, maintain correct polarity and use suitable shielded communication cable where required by the installation environment. Avoid routing communication conductors parallel to power switching conductors over long distances.

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