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Appendix C: Alvin Power Budgets

The following power budget is based on best estimates of amperes and on-time for loads of various buses. These estimates are subject to review for any specific dive. The power available for science, based on the following estimates, is 154 amp hours of 120VDC.

120V Outboard Bus
VB SW Pump 30 amps 20 min 600 amp min
VB Hydraulics 10 10 100
Hydraulic Pump 30 30 900
Port/Stbd Lift Thrusters 20 60 1200
Heading Thruster 10 30 300
Fwd Thrusters (3) 30 120 3600
Lights (10) (2 amps each) 20 120 2400
Inverter (Idle) .07 480 35
CTFM .6 60 35
Total 9170 amp min=153 AH

26V Inboard Buses - Service
CO2 Blower 0.4 amp 480 min 192 amp min
UW Phone (receive) 1.0 480 480
UW Phone (transmit) 17 40 680
Radio 2.0 10 20
Navigation 0.2 480 96
MBT Blow 1.2 5 6
MBT Vent 4 5 20
Emergency Light .01 480 5
Depth 1 .02 480 10
Releases 20 1 20
Total: 1529 amp min

 
26V Inboard Buses - Instrument
Imagenex (Science Use) 1.0 amp 0 min 0 amp min
Doppler Sonar 0.2 480 96
Port Strobe 10 2 20
Starboard Strobe 10 2 20
Fwd Strobe (1000 pics) 10 50 500
Acoustic modem .24 480 115
Depth 2 .02 480 10
Total: 761 amp min

26V Inboard Buses - Control
Motor Controllers 2 amp 120 min 240 amp min
Thruster/Pump Controller 2 120 240
VB Control 5 15 75
Port Manipulator 1.5 480 720
Starboard Manipulator 1.0 60 60
Hydraulic Control 1.0 60 60
Sci Power Control 1.5 120 180
Hold Bus 4 480 1920
Outside Light Control 1.7 240 410
Inside Lights 2 480 960
Total: 4865 amp min

26V Inboard Buses - Data
Video 5 amp 240 min 1200 amp min
Altimeter .02 480 10
Water Temp 1 .02 480 10
Water Temp 2 .02 480 10
Water Temp 3 .02 480 10
Gyrocompass 2 480 960
Data Collector 2 480 960
Attitude Sensor .04 480 20
Computer 4 480 1920
Total: 5100 amp min

26V Use Summary
Service 1529 amp min
Instrument 761
Control 4865
Data 5100
Total 12,255 amp min = 204 AH
26V power reflected to 120V bus:
204 AH x 26.5V = 5413 WH
5413 WH / 85% converter efficiency = 6368 WH
6368 WH / 120V = 53 AH from the 120V bus

120V Use Summary
Outboard Bus 153 AH
26V Load 53 AH
Total required to power sub:
Power available from batteries: 480 AH x 75% (depth of cycle)

Power available for Science (360-206) =
206 AH
360 AH

154 AH

Alvin Emergency Power Budget
Available Battery Capacity
Nominal capacity at 1 amp rate 4.5 Amp-hours
Additional factors:
Age
Temperature (0 deg C)
80%
85%
Remaining capacity (.80 x .85 x 4.5) = 3.1
Guaranteed pre-dive capacity:
Each RED battery
GREEN battery
85%
60%
Guaranteed total capacity:
Each RED battery (.85 x 3.1) = 2.6x2 =
GREEN battery (.60 x 3.1) =
5.2
1.8
Total all batteries: 7.0 Amp-hours

Power Usage
Equipment Current Drain
(amps)
Duration
of Use
Amp-Hrs
Expended
UQC Receive 1 2 hrs 2.0
UQC Transmit 17 7 min 2.0
Radio Receive 0.5 1 hr 0.5
Radio Transmit 3 5 min 0.25
Service Releases
Basket
Port Forward
Port Aft
Stbd Forward
Stbd Aft
20
20
20
20
20
4 sec
4 sec
4 sec
4 sec
4 sec
0.022
0.022
0.022
0.022
0.022
Sub Total: 0.111 AH
Dump Panel Releases
Port Manipulator
Stbd Manipulator
Buoy Release
Battery Tank A
Battery Tank B
Battery Tank C

8.2
8.2
20
8.2
8.2
8.2

70 sec
70 sec
2 sec
70 sec
70 sec
70 sec
0.159
0.159
0.011
0.159
0.159
0.159
Sub Total: 0.806 AH
MBTBlow Valves 1.2 5 min 0.100
Total Power Expended: 5.766 AH

Note: CO2 Srubber Operation
Fast 0.13 amp-hrs/10 minutes of operation
Slow 0.07 amp-hrs/10 minutes of operation

Last updated: April 16, 2008