Dual & Self powered OC&EF Protection Relays

The SIA-B is Dual & Self powered Overcurrent and Earth Fault Protection Relay, using the operating current through three specific current transformers fitted on the lines.

Data Sheet

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    Thanks to this adaptation, the SIA-B relays offer reduced dimensions, making this relay easy to install, and its lightweight helps the customer to save costs in transport.

    SIA-B is suitable for RMUs, SF6 insulated, and compact switchgear in those installations where the space is critical, making the maintenance much more manageable.

    USB front port connection (ModBus RTU protocol) for local communication. Remote communication through rear RS485 (ModBus RTU)

    These transformers are also used to obtain current measurements with the advantage that SIAB relay can also be used with auxiliary power supply (24 Vdc, 110 Vac or 230 Vac). The equipment can be occasionally supplied by an external battery portable kit (KITCOM).

    • Dual & Self powered OC&EF Protection Relay using the operating current through specific current transformers fitted on the lines. These CTs are also used to obtain current measurements.
    • Stores up to 100 events and DFR (4 fault reports in data format) in non-volatile RAM memory without power supply thanks to its internal RTC (Real Time Clock).
    • 1 input, LEDs and Configurable outputs thanks to Programmable Logic Control (PGC).
    • Test menu allows the trip circuit to be tested before the transformation center is powered up.
    • Bistable magnetic indicator which indicates the trip condition, maintaining its position even though the relay loses the supply (flag).
    • Self diagnosis of the status (WATCHDOG) through led.
    • Internal Commissioning battery as optional. (Lithium battery: 20 years lifetime).
    • High electomagnetic compatibility (EMC).
    • Low power consumption (0.5 W, 24 Vdc).
    • In Self powered mode, SIA-B starts-up from 0.4 times of primary three phase current.
    • USB front port connection (ModBus RTU protocol) for local communication. Remote communication through rear RS485 (ModBus RTU)
    • Its compact size makes SIA-B really easy to install and its light weight helps the customer to save costs in transport.

    50 Instantaneous phase overcurrent

    51 Inverse time overcurrent

    51N Inverse time calculated neutral overcurrent

    49T External trip

    50N Instantaneous calcalated neutral overcurrent

    49 Thermal image

    49T External trip

    PGC Programmable logic control

    TB Trip Block for switch disconnector

    Communication Software for SIA & SIL protection relays

    The SICom PC software has been designed and programmed to gain access to all of Fanox relays information, to modify the settings and configuration, check states and measurements and to analyse and save events and fault reports using a graphic-friendly user interface.

    SICom software works with the Windows® Windows 7, Windows 8, Windows 8.1 and Windows 10 operating system.

    • General data reading: Complete model, Version, Serial number, etc.
    • States reading
    • Measurements reading
    • Reading and changing settings
    • Reading and changing configuration
    • Reading and deleting events
    • Reading and deleting fault reports
    • Reading and deleting demand current (load data profiling)
    • Reading and saving oscillographic records in Comtrade format
    • Changing the user passwords
    • Saving and Loading settings files
    • Saving and Loading configuration files
    • Saving events and fault reports
    • Saving demand current (load data profiling)
    • Date-time synchronization
    • Configuring the communication parameters
    • Reading and changing counters
    • Commands for opening and closing the circuit breaker and block/unblock the recloser
    • Configuration of the inputs
    • Configuration of the outputs
    • Configuration of the causes that start a Fault Report

    The update of the software does not require any user´s action, this is, if the computer is connected to Internet, SICom updates itself when it is started.
    It will allow you to prepare all the settings and relay configurations without having the relay connected to the PC (offline mode), reducing engineering and commissioning time.
    SICom program uses Modbus protocol, so only the ports with this protocol can be used to establish the communication.

    SIA RANGESIA-B Specific CT'sSIA-B Standard CT'sSIA-C Standard CT'sSIA-F
    Auxiliary Supply24Vdc
    24-230 Vac/dc24Vdc
    48 Vdc
    110-230 Vac/Vdc
    24-220 Vcc / 48-230 Vac
    Self Power Supply3.2 A for CT08-5 6.4 A for CT16-5 12.8 A for CT32-5 25.6 A for CT64-5 51.2 A for CT128/5 102.4 A for CT256/5 (x3)0,075 In (x3)0,1 In (x3)
    External batteryUSB cable / Power bankUSB cable / Power bankKITCOMUSB cable / Power bank
    Internal battery√ (*)√ (*)
    Consumption0,5 W1,5 W0,5 W1,5 – 2,2 W
    CTSpecific CTStandard CT/1A - 2VAStandard CT/1A - 2.5VA Standard CT/5A - 5VAStandard CT/1 - 0,5VA Standard CT/5A - 0.5VA
    74TCS 1
    Trip Block111
    68 Zone Selection interbloking111
    PGCProgrammable LogicV3V3V3V3
    Sett. Group243/43
    Inputs--- EXT.TRIP3 DI--- EXT.TRIP 2DI 2DI + EXT.TRIP--- 2DI
    Outputs--- 2NC-NO3 NC-NO--- 2 NC-NO 3 NO1 NO + 1 NC-NO
    Output for STRIKER24 Vdc – 135 mJ24 Vdc – 135 mJ24 Vdc – 135 mJ
    LEDs2 LEDs 2 LEDs +1MAG.FLAG4 LEDs3 LEDs + 1 MAG.FLAGS 3 LEDs + 3 MAG.FLAGS3 LEDs configurable
    HMI20X2 LCD + 7/8 keys20X2 LCD + 8 keys20X2 LCD + 7/8 keys20X2 LCD + 7 keys
    Fault Report420204
    Oscillography10 records x 50 cycles10 records x 50 cycles1 record x 22 cycles
    Current demand
    Local Port (frontal)USBMicro USBRS232USB
    Remote Port (rear)RS485RS485RS485RS485
    Communications ProtocolsModBus RTUModBus RTU ModBus RTU or DNP3.0ModBus RTU ModBus RTU or IEC60870-5-103ModBus RTU DNP3.0
    Size of (HxW)Vertical: 120,65 x 167,80 mm
    Horizontal: 185,80 x 102,7 mm
    90 X 245 mmVertical Compact: 177 x 155 mm
    Vertical Standard: 177 x 189 mm
    Horizontal: 177,8 x 290,3 mm
    167,80 x 120,65 mm

    Related Products

    Advanced OC&EF Self-Powered Relay

    SIA-B is the most reliable dual powered (Self-Powered + Universal Vaux) relay offering a high performance previously available only in relays with Vaux:

    Remote communications for SCADA (Modbus or DNP3.0 protocols)

    • Up to 10 COMTRADE records
    • Advanced protection functions
    • Completely configurable I/O thanks to advanced logic

    Ultra-fast SOTF
    Very low start-up levels and minimum consumption <2 VA
    Compact design

    Ansi Code Functions

    50, 51, 50G, 51G, 49, 46, SHB, 49T, TB, 52, 50BF, CLP, 68, PGC

    Dual & Self-Powered OC&EF Protection Relays

    Counting with an extensive experience of successfully operating devices in the field worldwide and thanks to these unique advantages, SIA-C enjoys top recognition among users all around the planet.

    Above all, the different mechanics available by model list make our SIA-C the best choice for our customers, covering all the needs of the market

    Remote communications RS485 Modbus RTU or IEC 60870-5-103

    • Self-Powered & Dual-Powered (Self+Vaux)
    • Standard CTs /1 or /5
    • Low start-up levels
    • Load data profiling
    • Self diagnosis (watchdog)
    • Non-volatile RAM memory (up to 1.024 events and 20 fault report), maintaining date & time even in SP mode, thanks to its internal RTC
    • With internal commissioning battery as optional
    • Withdrawable model as optional

    Ansi Code Functions

    50, 51, 49T, 51G, 50G, 46, 46BC, 49, SHB, CLP, 79, 52, 50BF, 74TCS, 60CTS, 68, PGC



    FANOX FTB/FTP test block allows testing the protection, control, metering and/or communication device of a facility connected to field switchgear, easily and safely, isolating the circuits fully and eliminating all risks for the user.

    • Maximum safety for the user.
    • Internal automatic CT short circuiting.
    • Single hand fully isolated plug.
    • Locking system for safest operation.
    • Possibility of horizontal or vertical mounting, respectively.