Bard WA721 - Manual (Page 18)

Manual 2100-425
Page 16
PHASE MONITOR
All units with three phase scroll compressors are
equipped with a 3 phase line monitor to prevent
compressor damage due to phase reversal.
The phase monitor in this unit is equipped with two
LEDs. If the Y signal is present at the phase monitor
and phases are correct the green LED will light.
If phases are reversed, the red fault LED will be lit and
compressor operation is inhibited.
If a fault condition occurs, reverse two of the supply
leads to the unit. Do not reverse any of the unit
factory wires as damage may occur.
PRESSURE SERVICE PORTS
High and low pressure service ports are installed on all
units so that the system operating pressures can be
observed. Pressure tables can be found later in the
manual covering all models. It is imperative to match
the correct pressure table to the unit by model number.
ADJUSTMENTS
Adjustable Delay on Make and Delay on Break
Timer
The potentiometer is used to select Delay on Break
time from 30 seconds to 5 minutes. Delay on Make
(DOM) timing on power-up and after power
interruptions is equal to 2 minutes plus 10% of Delay
on Break (DOB) setting:
0.5 minute (30 seconds) DOB =123 second DOM
1.0 minute (60 seconds) DOB =126 second DOM
2.0 minute (120 seconds) DOB =132 second DOM
3.0 minute (180 seconds) DOB =138 second DOM
4.0 minute (240 seconds) DOB =144 second DOM
5.0 minute (300 seconds) DOB =150 second DOM
During routine operation of the unit with no power
interruptions the compressor will operate on demand
with no delay.
Typical Settings for Dual Unit Installation:
Unit 1: DOB set at 2 minutes, and DOM is 132 seconds
Unit 2: DOB set at 4 minutes, and DOM is 144 seconds