Monitoring the generators. 

  The generators can be queried using the modbus protocol. The program that does this:

• Runs on galfas2. This as a connection to the generator ethernet
• source: svn/aosoft/src/Cummings/cgenlog.c .. see also cgen.c, Test/readMultiReg.c for debugging

Recent generator usage:

    The plots show the generator usage for:

• The last day (.pdf)
• the last week (.pdf)
• the last 2 weeks (.pdf)
• the last 3 weeks (.pdf)
• 
  

• the plots show the sum off all generators.
  
• top frame: Power output  vs time.
  
• 2nd frame: Fuel consumption in gallons/hour
• 3rd frame: Fuel rate vs output power.
  
• red line is a linear fit of gal/hour per MegaWatt output.
• bottom frame: Efficiency vs power output.
•  KWatts output for 1gal/hour consumption

• Top frame: Gallons used vs time. (for the time period selected)
• Bottom frame: Cumulative hours vs time for each generator

processing: x101/generator/cgenstatdaily.sc

Fuel deliveries and Fuel usage:

• The measurements using the stick and the generator fuel usage meter do not agree.
• The 4th column shows the stick measurement before and after the fuel was added
• Column 5 has the cumulative fuel usage from the generator meters (when the fuel was added).
  
• Column 6 has the fuel used between fuel deliveries, using the stick and the generator meters.
• The 7th column is the ratio of genMeterReading/stickReadings.
  
• The final column shows the daily consumption for the interval between fuel deliveries.
  
• the generator reads 20 to 35% more than the stick.

01dec13: Generator startup with site as load. (top)

• Top: generator state vs minutes fro startup.
• Each color is a different generator
• the y axis is the generator status (with labels on the left).
• All 4 generators start together, and then generators 4,3, and then 2 are idled.
• 2nd: generator output power
  
• each generator is plotted separately
• The light blue line is the sum of the 4 generators.
• The site was running at 300 KW prior to the power outage (from the site power monitoring)
• It took about 4 minutes for the generator output to reach 300 KW
• The actual outage occurred at 17:39:20.
• The telescope motion was stopped from 17:39:20 to 17:41:20.. so there is only 1 minute with no telescope motion.
• I wonder if the air conditioners take a few minutes to get up to full load?
• 3rd: fuel usage by generator
• the is gallons/hour Usage plotted every minute.
• bottom: Efficiency: (Kilo watt hours output) per (gallon/hour used)

Summary:

• On automatic startup (with site as load) all 4 generators start, and then get shed 1 at a time
• The shedding process takes 9 minutes
• The generator output took 4 minutes to return to the output prior to the outage.
• The telescope was only stopped for 1 minute
• It make take the air conditioners 4 minutes to come up to full output.

19Nov13: first look at data while sband transmitter is on. (top)

    Data was taken on 19Nov13 while the sband transmitter was in operation. They sband  was transmitting around 850 KWatts.

• Generators 2,3,4 were in use.
• Data was sampled every 10 seconds.
• Data in stored in binary (svn/aosoft/src/Cummings/cgen_test.dat

• Page 1: Power, power factor
  
• top: power vs time. The power is by generator. Each color is a different generator.
• middle: Power factor vs Power(by generator).
• I computed the power factor as KW/KVA.
  
• The generators don't compute the power factor until the power exceeds about 40KW.
• bottom: power factor (by generator) vs power
• the power factor is above .9 above 200Kw/generator.
• Page 2: Voltage (Phase to ground) vs time
• Each frame is a separate phase (a,b,c)
• I'm not sure it the voltage spikes are real.
• Page 3: Current vs time
• Page 4: Pressures, temperatures.
• Top: pressure vs time for each generator
• Middle: Oil temperature vs time.
  
• You can see the pressure decrease as the oil temperature increases.
• Bottom: Coolant temperature vs time
• Page 5: fuel consumption and efficiency (by generator)
  
• Top: fuel consumption (Gallons/Hour)  vs time by generator
• The fuel used is recorded with .01 gallon resolution. The lower rates are pushing this resolution:
• 10gallon/hour = .028 gallons/10 seconds. So we saw maybe 3 counts change/ 10 sec sample.
• Middle: Fuel consumption vs output power (by generator)
• Bottom: Efficiency vs power (by generator).
• The vertical scale is : KiloWatts generated by 1 gallon/hour fuel consumption
• It looks pretty level down to about 200 KW/generator (then we run out of data).
• Page 6:Cumulative Power,consumption, efficiency (combining all 3 generators).
• Top: power vs time.
• Middle: fuel rate (gallons/hour) vs output power.
• bottom: efficiency (KW for 1 gallon/minute) vs output power.
• Page 7: Power, consumption blowup at startup and full power (sum all generators)
  
• Top: power at startup
• red line is cooling pumps off, green is cooling pumps on.
• 2nd: fuel rate at startup
• cooling off: 26 gallons/hour,
• This looks like the no load fuel rate needed.
  
• cooling on, 31 gallons/hour
• 3rd: power at full power
• 2180 kilowatts.
• bottom: fuel rate at full power:
• 187 gallons/hour

Summary:

Performance for  the 3 generators combined:

171202: Gen 4 failure. (top)

    Generator 4 had been offline while its exciter windings were being rewound.
On 02dec17 generator 4 was tested after reinstalling the exciter. After being brought up, the generator failed with a short circuit error (extended status).

The plots show gen 4 failure (.ps) (.pdf):

• The generator data is sampled once a minute (so it can miss glitches).
• Top Frame: generator state:
• black: gen1, red:gen2, green:gen3,blue:gen4
• State values:
• 0- stopped
• 1- start pending
• 2-warmup at idle
• 3- running
• Gen2 was running the site.
• Gen4 warmup started around a little after 8am. around 8.2 (08:12) it was running
• it ran for 4 minutes and then stopped.
• 2nd Frame: Gen 4 phase to ground voltages.
• When gen 4 went to run mode, it had 2400 volts (phase to gound). This is the standard value for the generators,.
• After 4 minutes, the voltage dropped to around 100 volts.
• On the 5th minute it was stopped.
• Bottom Frame: Gen 4 amps
• for the first 3 minutes i run mode, no current was drawn from the generator
• The current jumped to 400 to 500 amps at the 4th minute (when the voltage dropped to 100 volts).
• My guess is this is when the generator was connected to the output bus.'
• The dashed line (5 minutes after going online), the generator extended status faults were:
• Short circuit
• emergency status.
• Generator 4 is now offline waiting with generator 1 for its primary windings to be repaired.
  

processing: x101/171202/gen4fail.pro

171205: sbTx pwr vs generator output pwr for 2017 (top)

    The sband transmitted power was plotted vs the generator output power for the year 2017.
Making the plot:

• Input the sband transmitted power for 2017.
  
• This was taken from the lro power meter log file.
• This is typically sampled once every 10 seconds.
  
• Input the generator data for 2017.
• Normally sampled once a minute when the generators are on.
  
• Interpolate the generator time to the sample time of the tx transmitter.
• I didn't worry about edge effects on the interpolation (since generator should be on if sbTx transmitting).

• Top frame: sband Tx power vs generator output power.
• To remove bad data points i used a data selection criteria:
• sband Tx power > 1 KW
• The efficiency of the sbTxTubes must be less than 50%:
• sbTxPower < (generatorPower - cooling power..70KW) *.5efficiency)
• Bottom frame:
• Ratio of txPower to (generator - cooling power)
• All points were included.. no data selection used.

Observations:

• The plot does not differentiate between the number of generators used. 
  
• 100 KW output power levels gave efficiencies around 10%.
• 800 KW output power levels reach 40% efficiencies.
• 400 KW output power levels.
  
• There is a second trace with higher efficiencies.
• This is probably the 1 klystron mode that we were running.
  
• It Probably also uses fewer generators.
• The sbTx power level will also depend on  how well the transmitter is tuned (hv and rf drive).
  
• > .6 efficiency. these are probably bad points...
• When computing the efficiency  i subtracted the cooling power from the generated power (70KW).
• This gives a closer idea of how the tubes perform.
  

171207: generator power vs sbTx beam voltage (top)

    AO lost public power after hurricane maria (20sep17). The outage continued into dec17. The sband  group would like to observe an object in mid december. The question is how many generators will be needed.

    The requirements/constraints for the experiment are:

•  generators 1 and 4 are not working and will not be available for the run.
• generators 2 and 3 are   available.
• I've heard people say that each generator can probably output 800KW each (doubt if this has actually been tried:).
  
• The site has been running about 300KW at night (building 2 ac off) and around 400 KW during the day,.
• The power consumption of the sbTx is determined by the beam voltage (the filament current is fixed).
• The sbTx beam voltage comes on at 36KV. It can then be raised gradually from that point.

    I searched through recent (1klystron usage)  sband tx logfiles  for when the beam voltage was first turned on. I wanted to plot beamVoltage versus the generator power output. This data had to overlap in time:

•  The generator power is only sampled once a minute.
• The sband log files are sampled much faster (especially when things are changed).
• when the operators bring up the sband Tx, they start at 36KV and then bring the beam voltage up pretty quickly.

    The best data set (beam voltage was not brought up really fast) was on 01sep17. This was a single klystron run looking at clementine.

The plots show the generator power and sbTx beam voltage vs time (.ps) (.pdf):

•  The black trace is the generator power. The left hand axis shows the generator power.
• The red trace is the sbTx beam voltage. The right axis shows the voltage levels.
• The dotted red horizontal lines are spaced every 5 KV in beam voltage.
• the * show were the data were sampled
• The beam voltage started to come up  at 20.26 hours.
• there was one generator sample while the beam voltage was being brought up (at 20.28 hours)
• The green lines flags the common generator and beam voltage sample
• The generator was outputting 550KW with the beam voltage at 46KV.
• This is not an ideal measurement. You'd much rather have the beam voltage stable for awhile in case there are any time offsets in the measurements (the generator is tied to ntp.. as well as the sbtx).
  

Summary:

• in 1 klystron mode, 45KV beam voltage took 550KW of generator power (using  3 generators).
• running with fewer generators would probably need less generator output power.
• Using 2 generators, it looks safe to bring the sbTx beam voltage up to 36KV (with the site using 400KW)
• You could then monitor the generator power while you slowly brought up the beam voltage.
• Assuming each  generator can output 800KW:
  
• If the site uses 400 KW, then with 2 generators there is 1200 KW of headroom for the sbtx usage.
• being a little more conservative, you might want to let the sbtx use 1000KW
• The beam voltage should probably kept to below 50 or 55KV.
  
• if you cranked up the rf drive power, you'd probably get lots more that the 60KW of   transmitted power people had been mentioning.
  
• In all of this I'm assuming:
• that the klystron  power consumption does not depend on the rf output power.
• that the cooling power consumption does not increase appreciably with the power output (most of the power is in the water pump and not the cooling fans?).

processing: x101/171207/sbtxBmV_genpwr_170901.pro

180309 generator 3 failure during hf test

• Page 1: generator  power, currents and voltages
• top frame: total output power vs hour of day
• 2nd frame: output power by generator
• black: generator 2
• red   : generator 3
• the active power from each generator are identical.
  
• 3rd frame: generator current by phase for each generator.
• red,green,blue: phase A,B,C current for generator 2 (these are the lower traces)
• pink,red,light blue: phase A,B,C currents for generator 3 (these are the upper traces).
• For each generator the currents for the 3 phases are the same.
• The currents for generator 3 are about 5 amps/phase higher than generator 2 currents
  
• Bottom frame: The phase to ground voltage for the 3 phases of each generator.
• the phase to ground voltages for generator 2 are 2422 Volts
• the phase to ground voltages for generator 3 are 2403 Volts (this explains the higher currents for gen 3).
  
• page 2: power factor
• Top frame: total output power.
• 2ndframe : power factor by generator
• powerFactor= activePower/ApparentPower(KVA)
• the power factor for gen3 is lower than gen2
• Bottom frame: phase angle between voltage and current.
• the phase angle is the arcCos(pf)=arcCos(activePower/kvaPower)
• the phase angle for generator 2 varies from 20 to 25 deg (pf=.95 to .9)
• the phase angle for generator 3  varies from 40 deg down to 30 deg. (pf .78 to .88)
• the lower power factor for generator 2 will require more apparent power to give the same output power.
  
• Page 3: motor temperatures and pressures
• Top frame: total output power.
• 2nd frame:  oil pressure by motor/generator set
• black is motor/generator set 2
• red is motor/generator set 3
• the dashed red line is when the low oil pressure warning occurred for mot/gen set 3.
  
• It looks like the low pressure warning occurs around 48.5 psi.
  
• 3rd Frame: oil temperature by motor/generator set.
• Bottom frame: coolant temperature by motor/generator set.
  
• the Dashed black line shows the Pre highTempWarning issued for mot/gen set 2
• the Dashed red line shows the Pre highTempWarning issued for mot/Gen set 3.
• It looks like the pre temp warning occurs around 213 degF
• A HighTemp warning for mot/gen set 3 occurred at 14:20 ..
• this caused gen 3 to shut down.
• gen 2 tried to take up the load, but it could not provide 1.2 MWatts. so it ended up also shutting down.

Summary

• generators 2,3 were used for an hf test on 09mar18. the site and 430tx remained on commercial power.
  
• The highest generator  output power was 1.25 Mwatts
• A low pressure warning occurred on gen3 around 13:45
• it looks like this is set at 48.5 psi.
  
• a pre Hightemp warning occurred
• gen 3 at 14:06
• gen 2 at 14:19
• This trip level is near 213F.
  
• looking at some generic fault codes for cummings generators:
• a Pre High temp Fault will cause the generator to be derated
  
• generator 3 went offline with a high temp fault at 14:21
• generator 2 went offline with a high temp fault at 14:22
• The low pressure warning is set at 47psi
• the pre HighTemp warning occurs at 213 F
• This causes a de rating of the generator.
  
• Generator 3 has:
• currents 5amps/phase greater than gen2
• VoltagesTo ground about 30Volts less than gen2
• A lower power factor (.78 to .9) than gen 2 (.95 to .92)
• Talking to the generator mechanic:
• the air circulation for the motor generators needed cleaning.. (he did that the next day).
• Some of my preliminary plots showed a large current difference between gen3 and gen 2.
• After some talking with mike, i found my plotting bug...
  

220920 - fuel usage during fiona

    The generators were turned on friday 16sep22 around noon in preparation for hurricane fiona. They ran continuously (23sep22 still going).

• Generator 4 was used to generate power starting 16sep22
• fiona passed close to AO 18,19sep22.
  
• on 20sep22 around 8am the site switched to generator 1.
• The communication cards for generators 1,2,3 were damaged by a lightning strike  in aug22.
• gen 4 is the only generator that can be read remotely.
• We only have generator data for 16-20sep22 (while we were on gen4.

the plots show the generator usage 16-20sep22  (.pdf)

• Top: power vs date.
• Average value 218 KW.
• the power decreased for friday noon to friday evening and then stayed low.
• This may have bee weather related since 17,18,19sep had rain and the airconditioners were probably not using much power.
• 2nd: fuel rate:
  
• avg value 23.7 gallons/hour
• measurements during maria (more info)  showed that the meter reading are about 20% higher than the stick reading
• 3rd: fuel rate vs output power
• bottom: efficiency
• how many KW you get for 1gallon/hour vs the output power. The efficiency rises with total power till about 260KW where it gives about 10KW per 1gallon/hour

processing: x101/generator/fiona.pro

Yearly usage (top)

    Hour used and fuel consumed .. by generator and totals.

• 2014 (.ps)   (.pdf)
• 2015 (.ps)   (.pdf)   (thru 01dec15)
  

processing: x101/generator/chkusage.pro

Documentation:  (top)

• Modbus address definitions for generators (.pdf)
• This is page 19-21 of C673b.pdf
• The actual addresses start at 1 to 40001.
• Contains the state, nfpa110, and extended status codes
• cummings network information documentation directory   (local access)
  

history

• 2208xx - lightning strike blew out communication cards for gen1,2,3.. gen4 still works
• 220922 still waiting for cummings to come program the new cards so we can use them.
  
• 190907 - gen 4 burned out  the stator.
  
• gen 3 is still at cortes industrial being rewound. Should be back in 3 weeks
  
• 180925 - gen4 removed from array to be send to be re wound
  

home_~phil