Manual 2100-670I
Page
25 of 47
dirty the coil gets before an alarm is generated and how
many consecutive cycles before the alarm is triggered.
To change these settings:
1. Press MENU key to go to the Main Menu screen.
2. Press UP or DOWN keys and ENTER key to enter
TECHNICIAN password 1313.
3. Press UP or DOWN keys to scroll to
Adv System
Config
; press ENTER key.
4. Press UP or DOWN keys to scroll to
Dirty Cond
Alarm (B3)
; press ENTER key.
5. Press ENTER key to scroll to
Alarm Threshold
(see
Figure 40).
6. Press UP or DOWN keys to adjust the % restriction
to desired level.
7. Press ENTER key to save value and move the
cursor to
Trips before alarm
.
8. Press UP or DOWN keys to change the
Trips before
alarm
to the desired value.
9. Press ENTER key to save.
10. Press ESCAPE key several times to return to Main
Menu screen.
Compressor
Compressor Components
Compressor
Three Phase Scroll Compressor Start Up Information
Scroll compressors, like several other types of
compressors, will only compress in one rotational
direction. Direction of rotation is not an issue with
single phase compressors since they will always start
and run in the proper direction.
However, three phase compressors will rotate in either
direction depending upon phasing of the power.
Since there is a 50-50 chance of connecting power
in such a way as to cause rotation in the reverse
direction, verification of proper rotation must be made.
Verification of proper rotation direction is made by
observing that suction pressure drops and discharge
pressure rises when the compressor is energized.
Reverse rotation also results in an elevated sound level
over that with correct rotation, as well as substantially
reduced current draw compared to tabulated values.
Verification of
proper rotation
must be made at the time
the equipment is put into service. If improper rotation
is corrected at this time, there will be no negative
impact on the durability of the compressor. However,
reverse operation for over 1 hour may have a negative
impact on the bearing due to oil pump out.
NOTE:
If compressor is allowed to run in reverse
rotation for an extended period of time, the
compressor’s internal protector will trip.
All three phase compressors are wired identically
internally. As a result, once the correct phasing is
determined for a specific system or installation,
connecting properly phased power leads to the same
Fusite terminal should maintain proper rotation direction.
The direction of rotation of the compressor may be
changed by reversing any two line connections to the
wall-mount unit.
Compressor Control Module (CCM)
Delay-on-Make Timer
Short Cycle Protection/Delay-on-Break
Test Mode
High Pressure Detection
Brownout Protection with Adjustment
The LPC terminals are jumpered in this application.
Instead, the low pressure transducer is used for low
pressure monitoring.
Delay-on-Make Timer
In the event of power loss, a delay-on-make timer is
included to be able to delay startup of the compressor.
This is desired when more than one unit is on a
structure so that all of the units do not start at the
same time which could happen after a power loss or
building shutdown. The delay-on-make time period is
2 minutes plus 10% of the delay-on-break time period.
To ensure that all of the units do not start at the same
time, adjust the delay-on-break timer on each unit to a
slightly different delay time.
Short Cycle Protection/Delay-on-Break
An anti-short cycle timer is included to prevent short
cycling the compressor. This is adjustable from 30
seconds to 5 minutes via the adjustment knob (see Figure
41 on page 26). Once a compressor call is lost, the time
period must expire before a new call will be initiated.
10% of this time is also considered on the delay-on-
make timer (see above).
High Pressure Detection
High pressure switch monitoring allows for a lockout
condition in a situation where the switch is open. If the
high pressure switch opens, the CCM will de-energize
FIGURE 40
Adjusting Dirty Condenser Coil Alarm Settings
