Trane Ascend ACR C Series User Manual

AC-SVX003A-EN
83
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: Do not start a chiller “cold”. The oil heaters must be
in operation for a sufficient length of time prior to first
start.
Figure 29. Sequence of events: power up to starting
Confirm Presence
of Oil Within
90 Seconds
Confirm Presence
of Oil Within
90 Seconds
Confirm Presence
of Oil Within
90 Seconds
Power
Applied
* Lead Compressor (and its lead circuit) is determined by staging
algorithm – “Balanced”, “Circuit 1 Lead”, or “Circuit 2 Lead” selection
– also influenced by lockouts, restart inhibit, or diagnostics present.
On a manifolded circuit, GP4 will be the first to start and last to stop;
GP2 will not run by itself.
Fans pre-start,
EXVs moving to
Preposition
0 to 25 Seconds;
Compressor Delay Time
has expired
Power
Up
Power
Up
Symbio 800
Boot Time
(15 Sec)
Auto Mode commanded
by Front Panel or BAS
EXVs self-
close on
power up
Confirm Evaporator Water Flow
(6 Second Filter)
Enforce Restart Inhibit Timer
(0 to 1 minute)
Power Up Delay Inhibit Timer
(User Adjustable 0 to 30 minutes)
AutoAuto
Energize Evaporator
Water Pump Relay
Confirm Evaporator Water
Flow Within 20 minutes
(6 Second Filter)
Confirm Evaporator Water
Flow Within 20 minutes
(6 Second Filter)
Oil Heaters
Energized
when all
Compressors
on Circuit are
De-energized
EXV remains closed
Wait for Need
To Cool
(Diff to Start)
AutoAuto
Call for Cooling **
(Differential to Start is met)
Waiting
To Start
Waiting
To Start
Confirm
Presence of Oil
(0 to 90 seconds)
Waiting
To Start
Waiting
To Start
Send Start Command
to Lead Compressor*
Transition to
Running
Start Control of
Condenser Fan Flow
Pre-Position EXV of
Lead Circuit
Check Evap Pressure for
Low Pressure Cutout
Check Evap Pressure for
Low Pressure Cutout
Pre-Position EXV of
Lead Circuit
Check Evap Pressure for
Low Pressure Cutout
Confirm Presence
of Oil Within
90 Seconds
Power
Applied
* Lead Compressor (and its lead circuit) is determined by staging
algorithm – “Balanced”, “Circuit 1 Lead”, or “Circuit 2 Lead” selection
– also influenced by lockouts, restart inhibit, or diagnostics present.
On a manifolded circuit, GP4 will be the first to start and last to stop;
GP2 will not run by itself.
Fans pre-start,
EXVs moving to
Preposition
0 to 25 Seconds;
Compressor Delay Time
has expired
Power
Up
Symbio 800
Boot Time
(15 Sec)
Auto Mode commanded
by Front Panel or BAS
EXVs self-
close on
power up
Confirm Evaporator Water Flow
(6 Second Filter)
Enforce Restart Inhibit Timer
(0 to 1 minute)
Power Up Delay Inhibit Timer
(User Adjustable 0 to 30 minutes)
Auto
Energize Evaporator
Water Pump Relay
Confirm Evaporator Water
Flow Within 20 minutes
(6 Second Filter)
Oil Heaters
Energized
when all
Compressors
on Circuit are
De-energized
EXV remains closed
Wait for Need
To Cool
(Diff to Start)
Auto
Call for Cooling **
(Differential to Start is met)
Waiting
To Start
Confirm
Presence of Oil
(0 to 90 seconds)
Waiting
To Start
Send Start Command
to Lead Compressor*
Transition to
Running
Start Control of
Condenser Fan Flow
Pre-Position EXV of
Lead Circuit
Check Evap Pressure for
Low Pressure Cutout
** If Free Cooling is available, it shall be the first level control to start.
Total Free Cooling: balanced starts and hours or circuit x lead are available.
Start-up and Shutdown

Trane Ascend ACR C Series Specifications

General

Brand	Trane
Model	Ascend ACR C Series
Category	Chiller
Language	English