AC-SVX002C-EN
65
Power Up to Starting
The following diagram shows the timing from a power
up event to energizing the first compressor. The
shortest allowable time would be under the following
conditions:
•
No motor restart inhibit time left from subsequent
starts
•
Evaporator Water flow occurs quickly with pump on
command
•
Power up Start Delay set to 0 minutes
•
Need to cool (differential to start) already exists
•
Oil level is detected immediately
The above conditions would allow for a minimum
power up to starting the first compressor time of about
45 seconds (variations may exist due to options
installed). Note that it is not advisable to start a chiller
“cold”, the oil heaters should be in operation for a
sufficient length of time prior to first start.
Figure 47.
Sequence of operation: power up to starting
Power
Applied
Last Mode Was Auto
Auto
(Waiting for Evaporator
Water Flow)
Call for Cooling: Differential to Start is met
Energize Evaporator
Water Pump Relay
Confirm Evaporator Water
Flow Within 20 minutes
(10 Sec Filter)
Waiting to Start
Confirm Evaporator
Water Flow
(10 Second Filter)
Auto
(Waiting for
a Need to Cool)
Power
Up
Boot Time
(30 to 40 Sec)
Enforce Power Up
Start Delay Timer
(adj 0 to 10 mins)
Re-calibrate EXV
(overdrive closed)
*Lead Circuit/Compressor is determined by:
- Circuit Staging Option: Balanced Wear, Circuit 1 Lead, Circuit 2 Lead
- Compressor Staging Option: Balanced Wear, Fixed Sequence
(Follows per circuit configuration)
- also influenced by lockouts, restart inhibit and diagnostics present
Pre-Position EXV
of Lead Circuit*
EXV stroke to
Preposition
Waiting to Start
Start
Command
to Lead
Cprsr*
Waiting for
Differential to Start
Fan Pre-Start
of Lead Circuit*
Wait for Pressure
Stabilization
(3 Seconds)
Run
Inhibited