Relay Expansion Board (REB8)
- Aparna R R (Unlicensed)
- Anand Rajaraman
To expand the control relay capacity of the controller, use the Relay Expansion Board (REB8). This provides eight additional 2 Amp Form C dry relay outputs, rated for 24VDC. These relays are socketed and removable.
Figure 5-1: Relay Expansion Board (Physical View)
Up to five REB8s can be installed in an Mx or Mx-1-ME controller.
The wiring and settings of the REB8 are shown in Figure 5-2.
Figure 5-2: Relay Expansion Board (REB8)
Unlike the large heavy-duty door relays used to switch electric lock or strike power at 10 Amp loads, the expansion relays are normally used for signal level switching or pilot duty. Such switches, when closed, provide an input to a low-voltage sensing circuit like the one shown in Figure 5-3:
Figure 5-3: Alarm or Pilot Relay Circuit For Low-Power Switching
Some sensing circuit terminals also provide a power source. In this case, a separate power source (marked by an asterisk in Figure 5-3) is not required.
However, the switch can also be used to activate the coils of a remote heavy-duty relay like this:
Figure 5-4: Remote Relay Circuit for Heavy-Duty Output Device
The examples above connect across the NO and C terminals so no power is consumed when the device is in the normal state. This is the case in applications like elevator control where the control relays provide a contact closure to elevator control equipment only.
There is almost no distance limitation for the cable between the REB8’s terminal block and an isolation relay. If a powered device is being activated or energized, use the ScramblePad distance limitations (see Table 1-6 in section “ScramblePad/MATCH Inputs” as a good measure of distance capability. However, for accuracy, voltage drop calculations should be made for the specific load, cable, and distances involved, similar to lock calculations in section “Typical Door Relay Outputs”.
The REB8 is equipped with a Master Relay Override DIP switch. This switch can override all relays ON or all relays OFF. In the OFF position, relays cannot be activated by the controller until the Master Override OFF is returned to the normal operating position.
For information about the setup and installation of the REB8, see “Relay Expansion Board (REB8) Installation”.
Relay Expansion Board (REB8) Installation
To expand the output relay capacity of the controller, install the Relay Expansion Board (REB8). This board provides 8 additional 2-Amp (at 24VDC) Form C relay outputs.
REB8 Setup
The REB8 provides a set of jumpers (J1 through J8) to configure the address range assigned to these additional relays. The jumper is configured in this way:
J1 | Addresses 1 - 8 (factory default) |
|---|---|
J2 | Addresses 9 - 16 (for second REB8) |
J3 | Addresses 17 - 24 (for third REB8) |
J4 | Addresses 25 - 32 (for fourth REB8) |
J5 | Addresses 33 - 40 (for fifth REB8) |
J6 | Addresses 41 - 48 (for virtual sixth REB8) |
J7 | Addresses 49 - 56 (for virtual seventh REB8) |
J8 | Addresses 57 - 64 (for virtual eighth REB8) |
Amongst other things, these jumpers can be used for elevator control—where each address corresponds to an individual floor. Jumpers J6 through J8 specify virtual relays.
The REB8 is also equipped with a master relay override DIP Switch. This switch can override all relays to either the ON or OFF positions.
SW1 | OFF | Normal operating position. |
|---|---|---|
ON | Forces all 8 relays OFF so no system function can actuate the controller until the master override is OFF. | |
SW2 | OFF | Normal operating position. |
ON | Forces all 8 relays ON so no system function will actuate the relays until the master override is OFF. |
Only use the Master Override function for testing or troubleshooting.
REB8 Mounting
To install the REB8 expansion board:
1.Turn all system power off, remove connectors to the standby battery, then remove connectors to the AC power.
2. Install the board on the supplied standoffs and connect the EBIC5 cable as described in “Connecting Expansion Boards”.
REB8 Wiring
To connect outputs to this board:
1.Turn all system power off, remove connectors to the standby battery, then remove connectors to the AC power.
2. Punch out the knockout in the enclosure where you plan to route the wires. Either route these wires through the same opening you’re using for controller board connections, or knock out a new opening for wires going to the expansion boards.
3. Route the wires through the opening or knockout. If it makes wiring easier, detach each green connector from the board as you need it.
4. Loosen the screws on each connector plug you will be using.
5. Remove insulation from the wire and connect the specified wires into the green connectors at the required slots as described in “Connecting Wires to the Controller Boards”.
6. Tighten the screws until the wire is securely fastened in the slot.
7. If you detached the green connectors from the board in Step 3, push the connector into the appropriate socket until it locks into place, as shown in Figure 5-5. The connector and socket are keyed, so there is only one way to plug it in.
Figure 5-5: Connecting the REB8
8. Repeat this procedure for each wire you need to connect.
If a SNIB2 or SNIB3 is included in the expansion boards stack, make sure it is installed as the top board.
Testing the REB8
After installing the board, you can test it by following this procedure:
1.Attach a printer to the Controller or make sure the Controller is attached to a host PC.
2. Power the system up by first connecting AC then standby battery.
The system goes through its self-test. You should see this information printed out at the printer or displayed on the screen. Under the Configurations section, you should see this:
Expansion Relays = 8if one REB8 is installed and
Expansion Relays = 16if two REB8s are installed, and so on up to 5 boards. Under the Options section, you should see this line:
REB8-1if one REB8 is installed and
if two REB8s are installed, and so on.
3. Use Command 88*2 from the ScramblePad to request configurations and options information, or use Host PC software.
4. If the correct information doesn’t appear on the printouts, power down the Controller and recheck the EBIC connections, then retry the test procedure. If it still doesn’t work, contact Hirsch.