Installation manual

BHS AND REDS INSTALLATION MANUAL
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Two separate operating modes are possible:
Standard: no diagnostic digital input information about the Standby system is reported:
Input 1 = PS – No presence sensor signal for an interval that is too long
Input 2 = ENC – No encoder signal for an interval that is too long
Redundancy: diagnostic digital input information about the Standby system is reported. The
digital input diagnostic information of the active controller is replaced with the diagnostics of
both the controllers (3 inputs Active + 4 inputs Standby + 1 input for communication)
Input 1 = PWA – Failure of the power supply of the active unit
Input 2 = ENA – Failure (or warning) of active unit’s encoder signal
Input 3 = PSA – Failure (or warning) of active unit’s presence sensor signal
Input 4 = PWS – Failure of the power supply of the standby unit
Input 5 = ENS – Failure (or warning) of standby unit’s encoder signal
Input 6 = PSS – Failure (or warning) of standby unit’s presence sensor signal
Input 7 = SBC – Failure of standby unit controller
Input 8 = RSL – Failure of the communication over the redundancy serial line
NOTE
In the event the Standby unit is down (or missing), the status of all its
resources is declared OK, except for the Standby controller itself.
Host Interface
Each controller can connect to the host computer through various serial and Ethernet ports.
If the serial port is used, the host computer has to explicitly manage the switch over,
keeping the communications with the active controller. In this case, the reserved
redundancy digital output can be used to determine which controller is playing the active
role.
If the Ethernet port is used, two ways of interfacing to the host computer are possible
according to the IP address selection policy (the same as WebSentinel Interface):
- If the IP address is associated to the topology role (Working/Protecting), after the
switch over the host computer sees the data coming from a different IP address. It
will have to explicitly manage the switch over keeping the communications with
the active controller. In this case, the reserved redundancy digital output can be
used to determine which controller is active.
- If the IP address is associated to the redundancy role (Active/Stand-by), after the
switch over the host “sees” the data coming from the same IP address, but it
could experience (and should manage) a temporary disconnection due to the
timeout needed to refresh the ARP table on the host TCP/IP stack that remains
linked to the MAC addresses of the host itself.
Various alarms can be sent by REDS to the host computer through the standard
communication ports, based on the standard SC6000 diagnostics.