STC SmartScanIS, Руководство пользователя

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EUD-2016026-00 Rev.2, SmartScanIS User’s Guide for Union Pacific, 14 January 2021
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4.6.4.4 Relays
The SmartScanIS uses optically isolated solid-state relays (SSRs) to eliminate
electromagnetic radiation, which would otherwise be generated by arcing of mechanical relay
contacts. There are two SSRs. One SSR is used to operate the scanner shutters. The other
energizes the scanner heaters. The signals to activate the SSRs originate at the Processor
board.
The power rating for each SSR is intentionally overrated to ensure long-lasting reliability. For
example, the SSR associated with the scanner
shutters is rated for 100 VDC at 12 amps,
even though the shutters operate on 12 volts and require less than 2 amps each. Likewise,
the SSR associated with the
heaters in the 2100-510AC scanners is rated for 240 VAC at
25 amps of current, even though the heaters require only 120 VAC at 2.5 amps each.
4.6.4.5 Fuses
There are four heater fuses. All are 3AG glass-body 4-amp 250-volt fast-acting fuses. The
table below describes what each fuse protects.
Fuse Protects
F1 Heater for N/E bearing scanner.
F2 Heater for S/W bearing scanner.
F3 Heater for N/E wheel scanner.
F4 Heater for S/W wheel scanner.
There are four shutter fuses. All are 3AG glass-body 2-amp 250-volt fast-acting fuses. The
table below describes what each fuse protects.
Fuse Protects
F5 Shutter for N/E bearing scanner.
F6 Shutter for S/W bearing scanner.
F7 Shutter for N/E wheel scanner.
F8 Shutter for S/W wheel scanner.