Tyco Introduction to FACPs 4100U, Continued, 4.System Power Supply, Continued on next page

Introduction to FACPs (4100U), Continued

System Power Supply (SPS)

In the USA, a number of variants of power supply are available, e.g. SPS, RPS, XPS, XCharger each with different portions of circuitry (eg NACs, Battery Charger, IDNet) fitted or not fitted. In Australia, only one variant (SPS) is currently available, and it has hardware and software that are specific to Australia. This unit is used as the main power supply, but may also be fitted directly to a card bay as an expansion supply.

The system power supply (SPS) is mains powered and has backup batteries that get switched in on mains failure. It is the initial power source for the CPU and the host cabinet. The SPS provides 24V card power to the CPU motherboard and the other cards. It also supplies 24V power on a separate bus to the outputs, e.g. Notification Appliance Circuits (NACs).

The SPS also has three on-board NACs that support reverse polarity supervision. It provides an IDNet channel, auxiliary power, an auxiliary relay, and it mounts and drives the Alarm Relay Card.

The SPS performs functions such as brownout detect, battery transfer, battery recharge, earth fault detection, and power limiting of outputs. It provides voltage and current information to the CPU card, which can then be displayed at the user interface.

IDNET TERMINAL BLOCK (TB1) NAC TERMINAL BLOCK (TB2)

IDNET SHIELD JUMPER (P2)

CITY/RELAY CARD

TROUBLE INDICATION

JUMPER (P3)

DEVICE ADDRESS SWITCH (SW1)

AUXILIARY RELAY

TERMINAL BLOCK (TB4)

AUXILIARY POWER TERMINAL BLOCK (TB3)

CITY CARD	CITY / RELAY CARD
CONNECTOR (P7)	MOUNTING AREA

POWER/COMM TO NEXT PDI (P6)

POWER/COMM TO CPU MOTHERBOARD (P8)

BATTERY

CONNECTORS:

P4

P5

EARTH

FAULT MONITOR JUMPER (P1)

AC CONNECTOR (under board)

Figure 2-4. System Power Supply

Continued on next page

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