Panel Earth Ground Connections; Determining The Control's Power Supply Load - Honeywell VISTA-128BP Installation And Setup Manual

VISTA-128BP/VISTA-250BP Installation and Setup Guide

Panel Earth Ground Connections

In order for the lightning transient protective devices
in this product to be effective, the designated earth
ground terminal (terminal 30) must be terminated in a
good earth ground. Recommended wire gauge for the
ground connection is #16 AWG, run no farther than 30
feet. The following are examples of good earth grounds
available at most installations:
•
Metal Cold Water Pipe: Use a noncorrosive
metal strap (copper is recommended) firmly
secured to the pipe to which the ground lead is
electrically connected and secured.

Determining the Control's Power Supply Load

Use the tables that follow to calculate the total current
for the Auxiliary Power, the Alarm Output, and the
Polling Loop. In each table, multiply each device's
standby and/or alarm current by the number of units
used.
1. In Table 1, enter devices used on the polling loop.
Calculate total current draw on the polling loop.
Table 1: Total Polling Loop Current Draw
Polling Loop Device
(terminals 24 & 25 – 128mA) ✳
✳ The total current cannot exceed 128mA. If total load exceeds
128mA, then a 4297 Loop Extender Module can be used. Note
that the total number of points connected to the panel cannot
exceed 119.
3-36
WWW.DIYALARMFORUM.COM
Current # of Units Total
Polling Loop Subtotal
WWW.DIYALARMFORUM.COM
•
AC Power Outlet Ground: Available from 3-
prong, 120VAC, power outlets only. To test the
integrity of the ground terminal, use a three-wire
circuit tester with neon lamp indicators, such as
the UL-Listed Ideal Model 61-035, or equivalent,
available at most electrical supply stores.
The panel requires the earth ground
connection for its lightning transient protection
devices.
2. In Table 2, enter devices used on Auxiliary Power.
Calculate standby and alarm currents, then add to
get Auxiliary Power current subtotal.
Table 2: Auxiliary Power Current Load
Device Device Current X
Model # # of Units
Auxiliary Power Subtotal
(terminals 6 & 7 – 750mA max.)
Total Current
Standby Alarm