Host Interface; Power Supply - Datalogic SC6000 Installation Manual

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.

3.5 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 Sentinel 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.

3.6 POWER SUPPLY

Two separate paralleled power supplies are present to supply power both to the controllers and the
scanners. Under normal load conditions, the failure of one of the power supplies is tolerated by the
system. Voltage monitoring is present and used to generate alarms, however it does not affect the
switch over policy.