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Maintaining MX240 Host Subsystem Components

Maintaining the MX240 Host Subsystem

Purpose

For optimum router performance, verify the condition of the host subsystem. The host subsystem comprises an SCB and a Routing Engine installed into a slot in the SCB.

Action

On a regular basis:

  • Check the LEDs on the craft interface to view information about the status of the Routing Engines.

  • Check the LEDs on the SCB faceplate.

  • Check the LEDs on the Routing Engine faceplate.

  • To check the status of the Routing Engines, issue the show chassis routing-engine command. The output is similar to the following:

  • To check the status of the SCBs, issue the show chassis environment cb command. The output is similar to the following:

To check the status of a specific SCB, issue the show chassis environment cb command and include the slot number of the SCB. The output is similar to the following:

For more information about using the CLI, see the Junos OS documenation.

Replacing an MX240 Routing Engine

Removing an MX240 Routing Engine

Before you remove a Routing Engine, remove the cables that connect to it.

CAUTION:

Before you replace a Routing Engine, you must take the host subsystem offline. If there is only one host subsystem, taking the host subsystem offline shuts down the router.

CAUTION:

If the Routing Engine to be replaced is currently functioning as the primary Routing engine, switch it to be the backup before removing it.

To remove a Routing Engine from an SCB (see Figure 1):

  1. Take the Routing Engine offline gracefully.
  2. Place an electrostatic bag or antistatic mat on a flat, stable surface.
  3. Attach an ESD grounding strap to your bare wrist, and connect the other end of the strap to an ESD grounding point.
  4. Verify that the Routing Engine LEDs are off.
  5. Loosen the captive screws on the left and right of the Routing Engine.
  6. Flip the ejector handles outward to unseat the Routing Engine.
  7. Grasp the Routing Engine by the ejector handles, and slide it about halfway out of the chassis.
  8. Place one hand underneath the Routing Engine to support it, and slide it completely out of the chassis.
  9. Place the Routing Engine on the antistatic mat.
    Note:

    To maintain proper airflow through the chassis, do not leave an SCB installed in the chassis without a Routing Engine for extended periods of time. If a Routing Engine is removed, a replacement Routing Engine should be installed as soon as possible.

Figure 1: Removing a Routing EngineRemoving a Routing Engine

Installing an MX240 Routing Engine

To install a Routing Engine into an SCB (Figure 2):

  1. Attach an ESD grounding strap to your bare wrist, and connect the other end of the strap to an ESD grounding point.
  2. Ensure that the ejector handles are not in the locked position. If necessary, flip the ejector handles outward.
  3. Place one hand underneath the Routing Engine to support it.
  4. Carefully align the sides of the Routing Engine with the guides inside the opening on the SCB.
  5. Slide the Routing Engine into the SCB until you feel resistance, and then press the Routing Engine's faceplate until it engages the connectors.
    CAUTION:

    Align the Routing Engine correctly to avoid damaging it.

  6. Press both of the ejector handles inward to seat the Routing Engine.
  7. Tighten the captive screws on the left and right of the Routing Engine.
  8. Connect the management device cables to the Routing Engine.

The Routing Engine might require several minutes to boot.

After the Routing Engine boots, verify that it is installed correctly by checking the FAIL, RE0, and RE1 LEDs on the craft interface. If the router is operational and the Routing Engine is functioning properly, the green ONLINE LED lights steadily. If the red FAIL LED lights steadily instead, remove and install the Routing Engine again. If the red FAIL LED still lights steadily, the Routing Engine is not functioning properly. Contact your customer support representative.

To check the status of the Routing Engine, use the CLI command:

For more information about using the CLI, see the Junos OS documentation.

Note:

If enhanced IP network services is configured on the chassis, all routing engines must be rebooted after synchronizing the routing engines. For more information on synchronizing the routing engines, see Synchronizing Routing Engines.

Figure 2: Installing an MX480 Routing EngineInstalling an MX480 Routing Engine

Replacing an SSD Drive on an RE-S-1800

Each RE-S-1800 Routing Engine supports two solid-state drives (SSD) specified by Juniper Networks. The RE-S-1800 ships with one SSD installed in the slot labeled SATA SSD 1. The spare SSD is Juniper part number SSD-32G-RE-S. Figure 3 shows the arrangement of storage drive slots on a RE-S-1800 Routing Engine.

Figure 3: RE-S-1800 Storage Drive SlotsRE-S-1800 Storage Drive Slots

The following drive has been verified to work in the RE-S-1800 Routing Engine:

  • SSD-32G-RE-S

To replace a storage drive:

  1. Disable and deactivate the storage drive—press and hold the Online/Offline button till the LED starts blinking; wait till the RE LEDs are off.
  2. Remove the storage drive.
    1. Attach an electrostatic discharge (ESD) grounding strap to your bare wrist, and connect the strap to an ESD point on the appliance.

      For more information about ESD, see Preventing Electrostatic Discharge Damage in the hardware guide for your router.

    2. Unfasten the thumbscrew that secures the access door in front of the storage drive slots, and open the door.
    3. Slide the lock on the ejector to the unlocked position.
    4. Carefully slide the drive out of the slot.
  3. Reinstall a storage drive.
    1. Carefully align the sides of the drive with the guides in the slot.
    2. Slide the drive into the slot until you feel resistance, carefully ensuring that it is correctly aligned.
    3. Close the access door and tighten the thumbscrew to secure the door.

Replacing an SSD Drive on an RE-S-X6-64G

Replace the SSD Drives on an RE-S-X6-64G

Each RE-S-X6-64G Routing Engine supports two solid-state drives (SSD) specified by Juniper Networks. The RE-S-X6-64G ships with two SSDs installed in the slot labeled SSD1 and SSD2. Figure 4 shows the arrangement of storage drive slots on a RE-S-X6-64G Routing Engine.

Replacing an SSD drive in a RE-S-X6-64G Routing Engine consists of the following two stages:

  1. Replacing the SSD drives in the Routing Engine

  2. Copy the Junos OS to the newly replaced SSD

Figure 4: RE-S-X6-64G Storage Drive Slots RE-S-X6-64G Storage Drive Slots
  1

Extractor clips

  6

ONLINE/OFFLINE Button

  2

Auxiliary port (AUX)

  7

SSD LEDs—DISK1 and DISK2

  3

Console port (Con)

  8

Ports—USB1 and USB2

  4

Management port (MGMT)

  9

RESET Button

  5

LEDs—ONLINE, OK/FAIL, and MASTER

10

SSD card slot cover

Replacing the SSDs in the Routing Engine:

  1. Configure the set chassis redundancy gracefulswitchover, set system commit synchronize, set routing-options nonstop-routing commands to enable graceful switchover (GRES), commit synchronize (required for nonstop routing) and nonstop routing (NSR).
  2. Bring the backup Routing Engine (RE1) offline by pressing the ONLINE/OFFLINE button.
    Note:

    To disable and deactivate, press and hold the ONLINE/OFFLINE button until the LED start blinking and wait until all Routing Engine LEDs are Off.

    Note:

    If you have only one Routing Engine installed, you can bring it offline and follow the steps below. Traffic is interrupted when the Routing Engine is offline.

  3. From the backup Routing Engine (RE1), remove the SSDs from slot SSD1 and slot SSD2.
    1. Attach an ESD grounding strap to your bare wrist, and connect the strap to an ESD point on the appliance.

      For more information about ESD, see Preventing Electrostatic Discharge Damage in the hardware guide for your router.

    2. Unfasten the thumbscrew that secures the access door in front of the storage drive slots, and open the door.
    3. Slide the lock on the ejector to the unlocked position.
    4. Carefully slide the drive out of the slot. See Figure 5.
    Figure 5: Removing an SSD in the Routing Engine RE-S-X6-64G Removing an SSD in the Routing Engine RE-S-X6-64G
  4. Insert the new SSDs in slot SSD1 and slot SSD2. See Figure 6.
    Figure 6: Installing an SSD in the Routing Engine RE-S-X6-64G Installing an SSD in the Routing Engine RE-S-X6-64G
    1. Carefully align the sides of the drive with the guides in the slot.
    2. Slide the drive into the slot until you feel resistance, carefully ensuring that it is correctly aligned.
    3. Close the access door and tighten the thumbscrew to secure the door.

Copy the Junos OS to the Newly Replaced SSD Using a USB Stick (Minimum 8-GB)

  1. Insert the USB disk (with bootable image) in the USB slot on the Routing Engine.
  2. Log in to the backup Routing Engine (RE1) through the console session.
  3. Bring the Routing Engine online by pressing the ONLINE/OFFLINE button.
  4. After the Routing Engine starts booting from the USB, press y when you are prompted to confirm Install vmhost and Junos software on Primary and Secondary disk [y/N?] on the console. 
  5. After the installation completes, press y when prompted to confirm Reboot now? [y/N]? to reboot from the SSD disk.
  6. Once the backup Routing Engine boots:
    1. Verify the status of backup Routing Engine (RE1) is online by entering the show chassis routing-engine CLI.

    2. On the Routing Engine (RE1), verify the new SSDs capacity by entering the show vmhost hardware CLI. The output is similar to the following.

    3. On the backup Routing Engine (RE1), verify that the vmhost versions are same as Routing Engine (RE0) by entering the show vmhost version CLI. The output is similar to the following.

    4. From the primary Routing Engine (RE0), perform commit synchronize command.

    5. If the Network Services Mode: Enhanced-IP configuration was previously applied, then a warning message indicating the changes in the network services mode displays. Perform a reboot on the backup Routing Engine in order to enable the Network Services Mode to apply Enhanced IP.

  7. Make sure both the Routing Engines are in SYNC and ready for the switchover:
    1. On the backup Routing Engine (RE1), verify the GRES readiness by entering the show system switchover CLI. Output is similar to the following:

    2. On the primary Routing Engine (RE0), check the switchover state by entering the following command:

    3. On the primary Routing Engine (RE0), check the replication state if nonstop-routing is enabled by entering the show task replication CLI. The output is similar to the following:

  8. Switch the current primary Routing Engine (RE0) to RE1 by executing the request chassis routing-engine master switch command on the primary Routing Engine.
  9. Once the Routing Engine (RE1) becomes the primary Routing Engine and is carrying traffic, repeat the steps in Replacing an SSD Drive on an RE-S-X6-64G and Copy the Junos OS to the Newly Replaced SSD Using a USB Stick (Minimum 8-GB) on the new backup Routing Engine (RE0).
    Note:

    Make sure that each of the Routing Engine does not contain a mix of 50-GB and 200-GB SSDs. Both SSDs in any Routing Engine must be the same type and must contain the same disk capacity.

Replacing Connections to MX240 Routing Engine Interface Ports

Replacing the Management Ethernet Cable on an MX240 Router

To replace the cable connected to the ETHERNET port:

  1. Attach an ESD grounding strap to your bare wrist, and connect the other end of the strap to an ESD grounding point.
  2. Press the tab on the connector, and pull the connector straight out of the port. Figure 7 shows the connector.
  3. Disconnect the cable from the network device.
  4. Plug one end of the replacement cable into the ETHERNET port. Figure 8 shows the port.
  5. Plug the other end of the cable into the network device.
Figure 7: Cable ConnectorCable Connector
Figure 8: Ethernet PortEthernet Port

Replacing the Console or Auxiliary Cable on an MX240 Router

To use a system console to configure and manage the Routing Engine, connect it to the CONSOLE port on the Routing Engine. To use a laptop, modem, or other auxiliary device, connect it to the AUX port on the Routing Engine. Both ports accept a cable with an RJ-45 connector. If you want to connect a device to both ports, you must supply two separate cables.

Note:

We no longer include a DB-9 to RJ-45 cable or a DB-9 to RJ-45 adapter with a CAT5E copper cable as part of the device package. If you require a console cable, you can order it separately with the part number JNP-CBL-RJ45-DB9 (DB-9 to RJ-45 adapter with a CAT5E copper cable).

To replace a cable connected to a management console or auxiliary device:

  1. Attach an ESD grounding strap to your bare wrist, and connect the other end of the strap to an ESD grounding point.
  2. Press the tab on the connector, and pull the connector straight out of the port.
  3. Disconnect the cable from the console or auxiliary device.
  4. Plug the RJ-45 end of the replacement serial cable into the CONSOLE or AUX port. Figure 9 shows the external device ports on the Routing Engine.
  5. Plug the female DB-9 end into the console or auxiliary device's serial port.
Figure 9: Auxiliary and Console PortsAuxiliary and Console Ports

Upgrading to the RE-S-X6-64G Routing Engine in a Redundant Host Subsystem

A redundant host subsystem consists of a primary Routing Engine (RE0) and a backup Routing Engine (RE1). To upgrade the host subsystem to use the RE-S-X6-64G Routing Engine, you must first uninstall the backup Routing Engine and install the RE-S-X6-64G Routing Engine, which then becomes the backup Routing Engine. You then switch over this backup Routing Engine to make it the primary Routing Engine. Replace the other Routing Engine and configure it as the backup Routing Engine.

Ensure that the Switch Control Board in the chassis is SCBE2 or SCBE3 because the RE-S-X6-64G Routing Engine is not compatible with the Switch Control Boards SCB or SCBE. To upgrade the Switch Control Board to SCBE2, see Upgrading an MX240 to Use the SCBE2-MX, Upgrading an MX480 to Use the SCBE2-MX or Upgrading an MX960 to Use the SCBE2-MX, depending on the chassis on which the Routing Engine is being upgraded. To upgrade the Switch Control Board to SCBE3 Upgrading an MX240, MX480, or MX960 Router to Use the SCBE3-MX.

Note:

Save the router configuration before proceeding with the Routing Engine upgrade.

Note:

Nonstop active routing (NSR) and graceful Routing Engine switchover (GRES) are not supported during the upgrade and they must be temporarily disabled. Disable NSR by removing the nonstop-routing statement from the [edit routing-options] hierarchy level and by removing the graceful-switchover statement from the [edit chassis redundancy] hierarchy level .

Removing the Routing Engine

To remove the backup Routing Engine from the chassis (see Figure 10, Figure 11, and Figure 12):

  1. On the external management device connected to the Routing Engine, shut down the host subsystem by using the request system power-off command.
  2. Wait until a message appears on the console confirming that the operating system has halted.
  3. Remove the cables connected to the Routing Engine.
  4. Place an electrostatic bag or antistatic mat on a flat, stable surface. Attach an electrostatic discharge (ESD) grounding strap to your bare wrist and connect the strap to one of the ESD points on the chassis.
  5. Verify that the Routing Engine LEDs are off. Loosen the captive screws on the top and bottom of the Routing Engine.
  6. Grasp the Routing Engine by the ejector handles, and slide it about halfway out of the chassis.
  7. Place one hand underneath the Routing Engine to support it, and slide it completely out of the chassis. Place the Routing Engine on the antistatic mat.
Note:

To maintain proper airflow through the chassis, do not leave an SCB installed in the chassis without a Routing Engine for extended periods of time. If a Routing Engine is removed, a replacement Routing Engine should be installed as soon as possible.

Figure 10: Removing a Routing Engine from an MX240 RouterRemoving a Routing Engine from an MX240 Router
Figure 11: Removing a Routing Engine from an MX480 RouterRemoving a Routing Engine from an MX480 Router
Figure 12: Removing a Routing Engine from an MX960 RouterRemoving a Routing Engine from an MX960 Router

Installing the Routing Engine RE-S-X6-64G

To install the Routing Engine RE-S-X6-64G:

  1. Attach an ESD grounding strap to your bare wrist and connect the strap to one of the ESD points on the chassis.
  2. Ensure that the ejector handles are not in the locked position. If necessary, flip the ejector handles outward.
  3. Place one hand underneath the Routing Engine to support it and carefully align the sides of the Routing Engine with the guides inside the opening on the Switch Control Board SCBE2 or SCBE3.
    Note:

    The Routing Engine RE-S-X6-64G is supported only on the SCBE2 or SCBE3. RE-S-X6-64G is not compatible with the SCB or the SCBE.

  4. Slide the Routing Engine into the SCBE2 or SCBE3 until you feel resistance, and then press the Routing Engine's faceplate until it engages the connectors.
  5. Press both of the ejector handles inward to seat the Routing Engine. Tighten the captive screws on the top and bottom of the Routing Engine.
  6. Connect the management device cables to the Routing Engine. After the Routing Engine is installed, the ONLINE LED starts blinking green slowly.
  7. Replace the former primary Routing Engine, RE0, with the Routing Engine RE-S-X6-64G.
    Note:

    The Routing Engine RE-S-X6-64G is supported only on the SCBE2 and SCBE3. RE-S-X6-64G is not compatible with the SCB or the SCBE.

The Routing Engine might require several minutes to boot. After the Routing Engine boots, verify that it is installed correctly by checking the FAIL, RE0, and RE1 LEDs on the craft interface. If the router is operational and the Routing Engine is functioning properly, the green ONLINE LED on the Routing Engine lights steadily. If the red FAIL LED on the Routing Engine lights steadily instead, remove and install the Routing Engine again. If the red FAIL LED still lights steadily, the Routing Engine is not functioning properly. Contact your customer support representative.

Figure 13: Installing a Routing Engine in an MX240 RouterInstalling a Routing Engine in an MX240 Router
Figure 14: Installing a Routing Engine in an MX480 RouterInstalling a Routing Engine in an MX480 Router
Figure 15: Installing a Routing Engine in an MX960 RouterInstalling a Routing Engine in an MX960 Router

Verifying and Configuring the Upgraded Routing Engine as the Primary

After replacing the backup Routing Engine with the RE-S-X6-64G Routing Engine, perform the following steps:

  1. Verify that the SCBE2 or SCBE3 and RE-S-X6-64G Routing Engine are online by issuing the show chassis hardware command.
  2. After you install the RE-S-X6-64G Routing Engine into the SCBE2 or SCBE3, the Routing Engine gets automatically powered on and comes up in amnesiac mode as it is loaded with factory defaults. After the Routing Engine comes up in amnesiac mode, load the base configuration and commit.
  3. Configure the backup Routing Engine by using the commit synchronize command to copy the configuration to the backup Routing Engine.
  4. Use the request chassis routing-engine master switch command to make the Routing Engine RE-S-X6-64G (RE1) the primary Routing Engine. All FPCs reboot after this step.

Verifying and Configuring the Upgraded Routing Engine as the Backup

  1. Use the request chassis routing-engine master switch command to make newly installed RE-S-X6-64G (RE0) the backup Routing Engine.
  2. Use the commit synchronize command to copy the active configuration from the primary Routing Engine to the backup Routing Engine.

Upgrading to the RE-S-X6-64G Routing Engine in a Nonredundant Host Subsystem

In a nonredundant host subsystem, only one Routing Engine and one Switch Control Board are present in the chassis. When you are upgrading the Routing Engine, taking the host subsystem offline shuts down the router. To upgrade the host subsystem with the RE-S-X6-64G Routing Engine, you must uninstall the existing Routing Engine and install the RE-S-X6-64G Routing Engine. Ensure that the Switch Control Board in the chassis is SCBE2 because the RE-S-X6-64G Routing Engine is not compatible with the Switch Control Boards SCB or SCBE. To upgrade the Switch Control Board to SCBE2, see Upgrading an MX240 to Use the SCBE2-MX, Upgrading an MX480 to Use the SCBE2-MXor Upgrading an MX960 to Use the SCBE2-MX, depending on the chassis on which the Routing Engine is being upgraded. .

Note:

Save the router configuration before proceeding with the Routing Engine upgrade.

Removing the Routing Engine

To remove the Routing Engine from the chassis:

  1. On the external management device connected to the Routing Engine, shut down the host subsystem by using the request system power-off command.
  2. Wait until a message appears on the console confirming that the operating system has halted.
  3. Remove the cables connected to the Routing Engine.
  4. Place an electrostatic bag or antistatic mat on a flat, stable surface. Attach an ESD grounding strap to your bare wrist and connect the strap to one of the ESD points on the chassis.
  5. Verify that the Routing Engine LEDs are off. Loosen the captive screws on the top and bottom of the Routing Engine.
  6. Grasp the Routing Engine by the ejector handles, and slide it about halfway out of the chassis.
  7. Place one hand underneath the Routing Engine to support it, and slide it completely out of the chassis. Place the Routing Engine on the antistatic mat.
Note:

To maintain proper airflow through the chassis, do not leave an SCB installed in the chassis without a Routing Engine for extended periods of time. If a Routing Engine is removed, a replacement Routing Engine should be installed as soon as possible.

Installing the Routing Engine RE-S-X6-64G

To install the new Routing Engine (RE-S-X6-64G):

  1. Attach an ESD grounding strap to your bare wrist and connect the strap to one of the ESD points on the chassis.
  2. Ensure that the ejector handles are not in the locked position. If necessary, flip the ejector handles outward.
  3. Place one hand underneath the Routing Engine to support it and carefully align the sides of the Routing Engine with the guides inside the opening on the SCBE2.
    Note:

    The Routing Engine RE-S-X6-64G is supported only on the SCBE2. RE-S-X6-64G is not compatible with the SCB or the SCBE.

  4. Slide the Routing Engine into the SCBE2 until you feel resistance, and then press the Routing Engine's faceplate until it engages the connectors.
  5. Press both of the ejector handles inward to seat the Routing Engine. Tighten the captive screws on the top and bottom of the Routing Engine.
  6. Connect the management device cables to the Routing Engine. After the Routing Engine is installed, the ONLINE LED starts blinking green slowly.
  7. Verify that the SCBE2 and RE-S-X6-64G Routing Engine are online by issuing the show chassis hardware command.
  8. After you install the RE-S-X6-64G Routing Engine into the SCBE2, the Routing Engine gets automatically powered on and comes up in amnesiac mode as it is loaded with factory defaults. After the Routing Engine comes up in amnesiac mode, load the base configuration and commit.

The Routing Engine might require several minutes to boot. After the Routing Engine boots, verify that it is installed correctly by checking the FAIL, RE0, and RE1 LEDs on the craft interface. If the router is operational and the Routing Engine is functioning properly, the green ONLINE LED on the Routing Engine lights steadily. If the red FAIL LED lights steadily instead, remove the Routing Engine and reinstall it. If the red FAIL LED on the Routing Engine still lights steadily, the Routing Engine is not functioning properly. Contact your customer support representative.

Replacing the MX240 Craft Interface

Disconnecting the Alarm Relay Wires from the MX240 Craft Interface

To disconnect the alarm relay wires from the router and an alarm-reporting device (see Figure 16):

  1. Disconnect the existing wire at the external device.
  2. Attach an ESD grounding strap to your bare wrist, and connect the other end of the strap to an ESD grounding point.
  3. Using a 2.5-mm flat-blade screwdriver, loosen the small screws on the face of the terminal block and remove the block from the relay contact.
  4. Using the 2.5-mm flat-blade screwdriver, loosen the small screws on the side of the terminal block. Remove existing wires from the slots in the front of the block.
Figure 16: Alarm Relay ContactsAlarm Relay Contacts

Removing the MX240 Craft Interface

To remove the craft interface (see Figure 17):

  1. Attach an ESD grounding strap to your bare wrist, and connect the other end of the strap to an ESD grounding point.
  2. Detach any external devices connected to the craft interface.
  3. Loosen the captive screws at the left and right corners of the craft interface faceplate.
  4. Grasp the craft interface faceplate and carefully tilt it toward you until it is horizontal.
  5. Disconnect the ribbon cable from the back of the faceplate by gently pressing on both sides of the latch with your thumb and forefinger. Remove the craft interface from the chassis.
Figure 17: Removing the Craft InterfaceRemoving the Craft Interface

Installing the MX240 Craft Interface

To install the craft interface (see Figure 18):

  1. Attach an ESD grounding strap to your bare wrist, and connect the other end of the strap to an ESD grounding point.
  2. Grasp the craft interface with one hand, and hold the bottom edge of the craft interface with the other hand to support its weight.
  3. Orient the ribbon cable so that it plugs into the connector socket. The connector is keyed and can be inserted only one way.
  4. Align the bottom of the craft interface with the sheet metal above the card cage and press it into place.
  5. Tighten the screws on the left and right corners of the craft interface faceplate.
  6. Reattach any external devices connected to the craft interface.
Figure 18: Installing the Craft InterfaceInstalling the Craft Interface

Connecting the Alarm Relay Wires to the MX240 Craft Interface

To connect the alarm relay wires between a router and an alarm-reporting device (see Figure 19):

  1. Prepare the required length of replacement wire with gauge between 28-AWG and 14-AWG (0.08 and 2.08 mm2).
  2. Insert the replacement wires into the slots in the front of the block. Use a 2.5-mm flat-blade screwdriver to tighten the screws and secure the wire.
  3. Attach an ESD grounding strap to your bare wrist, and connect the other end of the strap to an ESD grounding point.
  4. Plug the terminal block into the relay contact, and use a 2.5-mm flat-blade screwdriver to tighten the screws on the face of the block.
  5. Attach the other end of the wires to the external device.
Figure 19: Alarm Relay ContactsAlarm Relay Contacts