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Wire Replacement mode

Will Baird
Will Baird
Updated

WireReplacement_image.png

Wire Replacement mode Data Sheet

Compatible Wire-Replacement radios

Master:
Slaves:

FGRIO-M

FGR2-IOS-CE-U
FGR2-IOS-C-U
FGR2-IO-IOE
I2-IOM-U I2-IOS-U


General Wire Replacement Notes:

  • Wire Replacement and Modbus polling are mutually exclusive.  It is one or the other.

  • Repeaters are NOT supported between the FGRIO-M and any of the slave units.
  • Network Diagnostics will not work with Wire Replacement.

  • Never connect a voltage source to a radio greater than the radio’s supply voltage. Doing so may cause irreversible damage to the radio and external equipment.

  • The FGR Wire Replacement Manual (LUM0008AG link below) should be used for the I2 radios.  The features and specs are identical.
  • Wire Replacement Masters:
    • See chart above.
  • Master DO cannot drive a relay because it doesn’t have current. It is logical only. However there are 2 specific relays that can create current:
    • See the  Driving Relays with FGRIO-M Digital Outputs (AppNote#5480) section below on how to setup and what relays to use.

      • Fairchild PN3569

      • Fairchild 2N3904

  • Analogue support:
    • 1-5 Volts
    • 4-20 milliAmps - Slave to Master only, though mA are not directly translated from Slave to Master.  They must be converted to 1-5 volts.

    • 250 ohm resistor can convert 4-20mA to 1-5 Volts.

      • But signal will still output as 1-5 Volts on other side of radio link.


FGR Wire replacement

  • FGRIO-M can have up to 4 IOS Slave radios connected, if each radio ONLY has a single DI or AI connection.   The FGRIO-M MUST be the master radio in a wire replacement network. The FGRIO-M Master support up to:
    • 4 Digital Out (DO)
    • 4 Digital In (DI)
    • 4 Analogue Out (AO)
  • FGR Slaves can be one of the slave radios in the chart at the top


I2 Wire Replacement

  • I2-IOM can up to 4 IOS Slave radios connected, if each radio ONLY has a single DI or AI connection.   The I2-IOM MUST be the master radio in a wire replacement network. The I2-IOM Master support up to:
    • 4 Digital Out (DO)
    • 4 Digital In (DI)
    • 4 Analogue Out (AO)
  • I2 Slaves can be the slave in the chart at top


Pulse Reading Dynamics .vs. Min/Max Packet Size

The minimum and maximum packet sizes determine the size of data packets in the frequency-hopping spread spectrum protocol. Settings the min/max packet sizes to 9 and 9 creates an update rate of both ends of the link just 6 updates per second. This means that the shortest pulse that can be reliably detected at both ends of the link is 1/3rd of a second.

Set the minimum and maximum packet size of the wireless signal replication network setting of 2/2. This provides the fastest hopping speed at 12 updates per second at both ends of the link. This equates to a pulse of 1/6th of a second to be reliably reproduced at both ends of the link.

Wire Replacement Quick Start:

  • Slaves configured as(0) Operation Mode ->(E) FGRIO-Slave.
    • Not compatible with Modbus.
  • Master configured as(0) Operation Mode →(E) FGRIO-Master
    • NOTE:  Master MUST be an FGRIO-M radio ONLY.  Cannot use an other IO radio as a Master.
    • NOTE: For the I2 (2.4 GHz) radio models, the Master MUST be an I2-IOM. Cannot use an other IO radio as a Master.
  • Enter Slaves SN in Masters Call book.  Do not uses dashes in call book.
  • Enter Master SN in Slaves Call Book. Do not uses dashes in call book.
  • Transmission Characteristics → Frequency Key must match for all aster slave units.
  • Transmission Characteristics → RF Data Rate should be set to 3 on both Master and Slave.
  • Transmission Characteristics → Slave Security should be Enabled on all Slave units.
  • Multipoint Parameters → Repeaters Should be set to Enabled on both the Master and Slave.
  • Multipoint Parameters → Subnet ID's should be "F" and "F" on both Master and Slave.
  • The masters IO Settings → Enabled IO must be set to enabled.
  • NOTE: Network Diagnostics will not work with Wire Replacement.
  • There is a connection when:
    • The Master CD light will ALWAYS be green, whether it is connected or not.
    • The TX light will also be solid red with or without a connection.
    • The Slaves 3 LED's all flash simultaneously.
    • The Master CTX light flashes red at about the same rate as the Slaves 3 LED's
    • Video of the LED pattern of the successfully linked Wire Replacement network

The Wire-Replacement LED patterns:

LED_Pattern_on_Wire-replacement.PNG

Wire Replacement Difference in the DI and DO

Between the FGRIO-M and theFGR2-IOS-CE-UorFGRIO-Sunits the DI and DO behave differently:

Slave:

  • DO: is a Contact Closure to Ground (CCtG) circuit.   When the DI from the Master is at 0 volts CCtG is enabled, when there is positive voltage on master DI the DO on slave is open.

  • DI: when Voltage is 1.7 or below the DO on the master 0.4 volts, when DI Voltage is above 1.8 DO on the Master is at 4.0 volts.

Master:

  • DI: When there is 0 volts on the DI master the DO on the slave CCtG.  When there is positive voltage, the DO on the slave is open.

  • DO: Actively drives low (0.4 volts) and high (4.0 Volts) but without any current (0.4 milliamps).

The DI voltage limits are:

  • Slave:   Whatever the Supply voltage is, so if you are using 24 volts power supply then the limit is 24 volts. With a 2 Amp limit.

  • Master:  0- 30 volts.

Driving Relays with FGRIO-M Digital Outputs (App Note #5480)

(PDF of this section below in Attached Document list)

Background

The FGRIO Master (FGRIO-M) radio is used in wire-replacement applications to wirelessly reproduce digital and analog inputs from a remote location. Wire replacement is also referred to as Signal replication. In some installations, users have a need to drive relay control switches. However, the drive strength of the FGRIO-M digital outputs is too low to drive the coil of a relay. The digital outputs can only drive up to 4mA and some relays require up to 200mA. This application note describes how to drive a relay with the FGRIO-M digital outputs.


Important Note:

Never connect a voltage source to a radio greater than the radio’s supply voltage. Doing so may cause irreversible damage to the radio and external equipment.


Results:

The drive strength of the FGRIO-M digital outputs is limited by internal circuitry. Specifically, a 330 ohm resistor is placed in series with the digital output. To overcome the series resistor, add a NPN bipolar junction transistor (BJT) to the FGRIO-M digital output. Using the transistor’s high current gain will allow the relay to be driven at its full current and voltage rating. Adding the transistor will also invert the logic signal from the FGRIO-M digital output. Ensure that the relay’s output connections are modified accordingly.

Add the transistor to the FGRIO-M digital output according to the wiring diagram in figure 1 by following these steps:

  1. Connect the base of the NPN BJT to the digital output.
  2. Connect the collector of the NPN BJT to the relay.
  3. Connect the emitter of the NPN BJT to signal ground

 

FGRIO-M_Driving_Relayus.png

 

Component Selection
For relays requiring drive strength below 200mA use part 2N3904 from Fairchild Semiconductor. The cost per 2N3904 transistor from Digikey (www.digikey.com) or call your local Radio Shack store for in-store availability). For relays requiring drive strength below 300mA use part PN3569 from Fairchild Semiconductor. The cost per PN3569 transistor from Digikey (www.digikey.com). Selection criteria for both transistors were low cost and high availability. In the unlikely event that higher current drive is required, select the NPN BJT accordingly. Calculate the transistor needs based on driving the transistor in saturation with less than 4mA.

Warranty:

Product                     
Warranty
Period
FGR2-IO-IOE
FGR2-IOS-CE-U
FGR2-IOS-C-U
FGR2-IOS-C-U-SR001		 3 Years
FGRIO-M 2 Years
I2-IOM-U 2 Years
I2-IOS-C-U
I2-IOS-C-U-SR010		 2 Years

 

End of Life Notice:

END OF LIFE : FGR2-IO Series

FreeWave can no longer obtain the component
parts necessary to build or repair these models.
Product Affected:  FGR2-IO Series
End-of-Life Date:  May 31, 2023

Models Affected (including all configurations):

  • FGR2-IO-IOE
  • FGR2-IOS-CE-U
  • FGR2-IOS-C-U
  • FGR2-IOS-C-U-S
  • FGRIO-M

 

FreeWave Tool Suite Management software for the FGRIO-M/FGR2-IO

FreeWave complimentary radio network management software

You can download Tool Suite 2.13.2 (which provides support for FGR3-IO product series) and its User Manual from the below link:

Note:  The system this is installed on must have Internet access during the installation, since the installer pulls libraries from the Microsoft site.

PDF Documents for the FGRIO-M/FGR2-IO Series of radios:

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