User manual

Digital Monitor AMC-1DBx Series User Manual
21
Table 4-8: USB Standard A-Type Connector Pin-out
Pin Signal
1 Vbus (power, +5V)
2 D+
3 D-
4 Power/Signal Ground
shell Chassis Ground
4.1.2.8 Real-Time Clock
The real time clock of the monitor has backup power provided by an on-PCBA power source.
The real time clock is initially set at the factory and arrives at the customer site with the time as
per the manufacturing time zone. The real time clock device may be powered off for as much as
6 mouths between manufacturing and initial customer commissioning. The real time clock will
survive power outages lasting weeks without loss of the current time.
A 24.5mm 3V (CR2450) lithium coin cell battery is provided on the PCBA to power the real time
clock in order to meet the objectives. The battery is replaceable in the field through a battery
carrier/socket provided. See Figure 4-8 Battery and Battery Holder for Real-Time Clock.
Refer to
Figure 4-3: Digital Monitor Components for the location of the battery holder.
Figure 4-8 Battery and Battery Holder for Real-Time Clock
4.1.2.9 Relays
The monitor is capable of supporting up to 16 relays within the enclosure for controlling HVAC
devices. Additional relays are available with remote devices.
The relays are connected to the monitor through 8 pin plugs. Refer to