Telecom Generator

TheBackRoads

Hey all,

Saw on the news this last week the following generator in a story about storm damage. I looked it up as it looks like a Honda EU3000iS but with "Alpha" tags on it. Google search found it. It's apparently a converted 3000iS but for 36/48V output for telecom. What's everyone's thought on this? Would it be worth it to find one, and use a secondary charge controller for running this genny for off-grid charging?


Generator Link

solarvic

Re: Telecom Generator

I have 2 of these. http://www.alpha.ca/web2/products/generators/item/alphagen?category_id=28 The ones I have are koehler powered. They are 48 volt. I never used them as I have a 24 volt system. I had a thread on here about how could I use them to charge a 24 volt system. Thinking of using a midnight charge controler to charge my 24 volt forktruck battery. solarvic PS= my generators are the 7kw 48 volt dc model.

vtmaps

Re: Telecom Generator

I don't know the answer to your question. I'm just responding to point out that Alpha now owns Outback. I wouldn't be surprised if Alpha comes up with a similar generator optimized for RE (as opposed to telecom) applications. --vtMaps

inetdog

Re: Telecom Generator

TheBackRoads wrote: »

Hey all,

Saw on the news this last week the following generator in a story about storm damage. I looked it up as it looks like a Honda EU3000iS but with "Alpha" tags on it. Google search found it. It's apparently a converted 3000iS but for 36/48V output for telecom. What's everyone's thought on this? Would it be worth it to find one, and use a secondary charge controller for running this genny for off-grid charging?


Generator Link

In both cases, using a DC to DC charger would potentially make for a more efficient use of the generator output. But the key would be to find a CC which is neither MMPT, nor PWM. The MPPT algorithm used for charging from panels might not be stable when fed from a generator, and PWM would waste power.

TheBackRoads

Re: Telecom Generator

Good info above. I'm not looking at buying anything, just saw the concept of a 48V generator and wondered about its feasibility with off-grid use. That's all 8)

stephendv

Re: Telecom Generator

One of the advantages of a DC gen is that you can charge with the gen and at the same time run your house off nice-clean power from your battery inverter rather than the usually dirty AC from the gen. The disadvantages are that you don't have a backup AC source incase the inverter has down time and you can't use the 'boost' functionality in some modern inverter that add generator power to inverter power.

If you had to choose between a DC gen or a Honda EU generator for the same price, the EU is obviously more versatile: You get nice clean AC and you can use it as a backup incase your inverter needs repairing/replacing. But if the DC was substantially cheaper, it could be an attractive option.

BillBlake

Re: Telecom Generator

solarvic wrote: »

I have 2 of these. http://www.alpha.ca/web2/products/generators/item/alphagen?category_id=28 The ones I have are koehler powered. They are 48 volt. I never used them as I have a 24 volt system. I had a thread on here about how could I use them to charge a 24 volt system. Thinking of using a midnight charge controler to charge my 24 volt forktruck battery. solarvic PS= my generators are the 7kw 48 volt dc model.

If they stay true to the 52 Volts DC Alpha talks about charging a 48 Volt bank may get slow and rough.
It's a bit far fetched in this case but if I really was insistant on using one of those gennies what about a fairly small
44 Volt battery bank.
Time the fuel supply to cut off the same as the sun must set - or come up with some battery charge regulation.

Then - Give Up the 5% to 10% Loss for a 48 Volt Inverter being used at no more than 1/3 capacity.

Then - Give Up another 10.6% - 11% Loss for a 'Yacht Type' State of the Art - 24 Volt Battery Charger that has

Active Power Factor Correction (PFC) and synchronized rectification output.

Bill Blake

TheBackRoads

Re: Telecom Generator

Just got a quote, you need to have a "business" but he said $2,209 for the device.

inetdog

Re: Telecom Generator

TheBackRoads wrote: »

Just got a quote, you need to have a "business" but he said $2,209 for the device.

You end up paying for high reliability and low volume production, I guess.

Donnytis

Re: Telecom Generator

TheBackRoads wrote: »

Hey all,

Saw on the news this last week the following generator in a story about storm damage. I looked it up as it looks like a Honda EU3000iS but with "Alpha" tags on it. Google search found it. It's apparently a converted 3000iS but for 36/48V output for telecom. What's everyone's thought on this? Would it be worth it to find one, and use a secondary charge controller for running this genny for off-grid charging?


Generator Link

The ALPHAGEN DCX3000 is not a converted Eu300is but a completely different D.C product, Alpha Technologies Co-engineered this product with Honda using the Eu3000 product as the starting platform. You should go to the alpha technologies generator http://alpha.com/outside-plant-power/generators. Solarvic mentions in this thread that he has 2 of these but powered by Kohler. Those would be ALPHAGEN 5K or 7.5K curbside stationary generators, LPG /Natural gas powered. the ALPHAGEN DCX3000 is a gasoline powered portable, D.C 36/48VDC (switchable). The Alpha website has manuals you can download for further info. I can provide more technical information if you need.


NOTE: The poster works for Alpha.

new2PV

Can the dcx3000 be connect to a mppt controller? How is the voltage regulated? Is 52.5 volts the max? .How can we get into absorption and float? Will it damage flooded batteries charging at reduced voltage? Can it be directly connected to an inverter?

inetdog

new2PV wrote: »

Can the dcx3000 be connect to a mppt controller? How is the voltage regulated? Is 52.5 volts the max? .How can we get into absorption and float? Will it damage flooded batteries charging at reduced voltage? Can it be directly connected to an inverter?

It is generally not a good idea to try to connect a regulated voltage source to an MPPT controller unless the source can produce a good bit more power than the CC or GTI actually needs.
Otherwise the search algorithm will deliberately load the generator into a range where the output voltage starts to drop rapidly. At that point the generator will be overloaded.
Some MPPT algorithms could even cause an overload during the scan process even if the source has extra capacity compared to the long term MPPT target.

new2PV

Thanks for the answer, but do you think this generator could be modified to act as a proper charger, and why would they not make it with the proper voltages?

Vic

Hi new2PV,

These DC generators are not inexpensive, and appear to be designed for a specific Telecom application.

An MPPT CC needs a reasonable amount of headroom, in order to function properly. A 52.5 V input to an MPPT CC charging a 24 V battery would seem more reasonable ... but, many MPPT CCs are designed, knowing that the power source (usually PV modules) are inherently current-limited, DC gensets and power supplies are not. So the CC might be at risk, if it needs to limit its current, especially during some fault condition.

Sometimes, placing a resistor in series with the + Vin to the CC will reduce this above noted risk, but this reduces the efficiency of the charging system. Such a resistor might help an MPPT CC find a good Max Power Point, because the power source is less stiff (higher impedance).

boB, on the MidNite Forum, has mentioned this possible risk to MPPT CCs.

For Flooded and AGM batteries, 52.5 V will do a reasonable amount of charging customary deep-cycle Flooded batteries, and, perhaps AGMs as well, but there are probably better, and less expensive approaches ... IMO. FWIW, Vic

new2PV

What about using a PWM wind charge controller connected to the generator? Or how about a diode in the postive line to the battery and a resistor across the diode. The generator will still supply current to the load, but it wont be able to sense the voltage back through the diode. The resistor across the diode will bring the sense voltage back the generator but it will be a lower number due to the resistance. If the generator sees the voltage is low it will try and raise the voltage/current until it see's 52.5 volts, but the voltage at the battery maybe much higher..how high I don;t know. However, there will be a 52 watt power loss across the diode in the form of heat If we have 52 amps flowing in the circuit with a forward 1 volt drop. The generator must see 42-55 volts or it will have no output. Above 56 volts it will shut off after 1 second.

Brlux

There is one of those for sale near me.
http://phoenix.craigslist.org/wvl/hvo/5020764496.html

new2PV

Way too much money They were on ebay for $329, but they are all sold out now..I would never spend that much for one for what he wants. Question is can we actually use these things?

Vic

New2,

BTW, it appears that this DC genset is a Manual Start model, and has a Manual Choke. So, this further limits the versatility, along with the too-low output voltage.

And, based on your possible interest in Gen Support, this genset, of course, would be of no direct use.

If someone gave one to you, it still might not be worth your time. It is possible that one could hack the voltage regulator, depending on how that function is implemented, but, there are so many other options that require no hacks.

Opinions, FWIW, Vic

new2PV

A friend of mine has a Alphagen and directly connected it to the inverter after starting it up on batteries, and then disconnecting them. No issues with the inverter, maybe the DC signal is pretty good out of this unit?

new2PV

Test the Alphagen on my system today, works real good, and it actually shuts off when the voltage hits 57 volts, I just need to get a auto start installed in it. It works well with the charge controller providing the 57 volts charging rate, and the 52 volts bulk coming from the generator Put a 2000 watt load on it, like it was nothing to it...

new2PV

This thing is really quiet, for those who suggested to stay away from these units i don;t know why you would NOT want one... You can put the 57 volt charge on the next day via your solar panels.. in a hurry, with generator assist.

MarkP

I just bought one and have been using it for a couple of days now because my family was visiting and solar couldn't keep up.  This thing is a champ.  I ran it 9 or 10 hours per night (one of our party had asthma-like conditions and running a dehumidifier really helped).  Huge fuel tank would last a couple of nights.  The unit is extremely quiet like its cousin the eu3000i.  It got rained on one night with no visible ill effects.


If left on indefinitely it would probably charge your batteries up to the roughly 90% SOC range and the last few percent would be painfully slow so it is not a "charger".  I spoke with the Alphagen guys and they confirmed that the design is aimed at being able to drop one of these off the truck at a remote site, plug it into the battery bank, and leave it running for many hours without overcharging the batteries, and that they did not build in any smarts beyond that.  They picked a voltage (52.5 volts) that would keep the batteries relatively happy sort of towards the upper end of their range of SOC.  It does respond to the increasing voltage of the batteries by throttling back.  I have it on now and I noticed it gradually decrease power over several seconds.  Turns out the sun came out and the panels are now doing most of the work.  You can hear it suddenly throttle up when the reefer or microwave comes on.  If you were to unplug it the speed drops to an eco-idle speed.    The specs say it has a permanent magnet generator so I figure that means voltage is linked to rpm.  Other changes with load are merely throttle changes not speed changes as far as I can tell so it seems not to have an eco setting beyond dropping to idle when no power at all is needed.  The Alphagen tech said it's like a lawnmower in that you must manually start and stop it.  I asked whether the output voltage could be adjusted and he said no, although he may have been instructed to dissuade customers from fiddling with the controls.


All in all it's great and I can't imagine why anybody with a 36 or 48 volt system wouldn't snap one up.  Let your solar panels do the fancy charging.  This will keep your batteries 90% of fat dumb and happy overnight or through periods of no sun.

MarkP

I turned off the generator because solar was pumping.  My charge controller is showing steady green now.  I just tried starting up the generator again to see how it behaved and it stayed at idle, presumably because the battery voltage is above 52.5 volts.

new2PV

I actually converted mine to ac with eu3000is parts, but it worked better on dc, gen support is horrible with a small gen on ac. If you need any spare parts for it I am willing to sell them cheap. I now have auto choke and electric start and it works just ok, and i can charge the batteries. However I can;t use large loads as I could use with DC.

MarkP

I first became aware of this unit while researching DC generators for the purpose of directly feeding the batteries since the smaller eu2000i would often not keep up and would cause the UPS/inverter to switch back to battery power.  This incompatibility was a PITA and I resolved to either get an eu3000i or a direct DC generator.  In the DCX3000 I have both, sort of.  I got it at a good enough price that there is no point in quibbling over not having an AC generator.  I only use it while I am home and can manually turn it on.  I suppose that after I have been at this long enough I will decide I need auto start but for now I only need back-up generation when I am home and using a lot of power, so this fits the bill perfectly.

MarkP

It does have some quirks.  There is a battery interface cable with leads about 3 ft long that attach to the poles of the batteries on one end and have a grey Anderson SPE80 connecter on the other end.  There is also an output interface cable with a red SPE on the end that plugs into the generator and a grey SPE80 that connects with the one on the end of the battery interface cable.  There are three lengths for the output interface cable, 10', 30', and 50'.  All conductors are #6 gage.  I was initially glad to have received the 50' cable since it seemed most versatile and since it was undoubtedly expensive I felt like I had scored somehow.  However my calculations show that the voltage drop through 100' of #6 wire at 55 amps is 2.2 volts!  So even when running in the middle of the range at 25 amps the generator is actually delivering 1 volt less than it thinks it is.  The penalty is significant because as the current through the cables increases the battery bank sees less and less voltage coming from the generator.  The battery bank must discharge down to whatever voltage is actually getting through at the battery end and until it does the generator is only carrying part of the load and of course as the battery voltage goes down the current from the generator goes up, further aggravating the condition.  Later after the loads decrease the generator slowly replaces what came out of the battery but I find it all very unsatisfying.  My Morningstar charge controller increases the absorption period if the voltage drops below 50 volts overnight, and I was seeing 50.4 volts at the batteries even though the generator was producing 51.6 volts at its end.  The voltage would have to be under 50 before the generator was fully loaded.  In short the response of the generator to load increases is somewhat muted.  This phenomenon must be greater when using a 50' pair of #6 than when using say a 10' pair of #2/0.  Also this is on top of the fact that I seem to be getting only 51.6 volts at the generator output rather than the 52.5 the generator is labeled for.  I alluded to the possibility that there was a voltage output adjustment somewhere or somehow.  The fact that the tech told me no does not completely deter me.  He would undoubtedly keep such info from the un-initiated.  Another possibility is that there may be a connection where voltage sense wires from the output terminals are landed to let the control board know what the output voltage is.  If there is and I can find it I can just add a twisted pair of light gage wire to the output cable and land them on the battery terminals.  Then I could keep the cable 50' long and it would only cost me a little gas, but the batteries would be held at a steady voltage.


It seems my options are:

1. Live with it.  It works pretty good as is.

2. Cut cables way short.  Get larger conductors or double up using multiple lengths of the #6.  Eliminate the grey SBE80 connectors and terminate directly onto the batteries.  Betcha that would count as a few feet of #6.

3. Find the pot that adjusts output voltage and turn it up.  There must be a control circuit for this.  I now think that I hear subtle speed changes as the generator increases throttle to maintain the output voltage at higher load.  This would be necessary to compensate for losses in the windings.  The question is whether there is a manual adjustment and whether I can find it.

4. Find where on the control board the output voltage is landed, assuming it is something that can be isolated, and detach it from the output.  By adding conductors to the output cable, sense the battery voltage  at the battery posts rather than at the generator output.

5. While I'm at it, increase the size of all wiring in my battery string as well as too and from it.  The APC SmartUPS 3000 I am using came with a 100 amp fuse.  I had a supply of #4 stranded.  That's what I used everywhere.  I don't think it will burn up before the 100 amp fuse does but it turns out that my system is very sensitive to voltage drop given the limitations of the DCX3000.

Which has more resistance, a 100 amp fuse or a 100 amp breaker?

new2PV

The voltage may not be adjustable as the inverter is encased in epoxy, and not sure how to get it out without destroying it.

MarkP

I was hoping you might have insight newPV2.  In the spirit of looking a gift horse in the mouth though, does the DCX3000 have an inverter?  Are you thinking of the additional parts that the eu3000i has?

new2PV

The dcx3000 has a ac field the inverter built in changes it to dc. The eu 3000 converts ac to dc then back to ac with a stable 60 hz frequency not dependant of rpm.

dcx3000

Looking for more information and possibly pictures on how to modify these alphagen dcx3000 generators.  I will begin the teardown of one of my generators if there are people that can assist.  The goal being to produce amps from one of these for direct charging and not load sensitive even if the load at idle can be increased to produce more amps.

I would like to charge with them at around 60-80amps and need a solution.

BB.

What would you like to do with/change on the genset? Generally, as I recall, these gensets output a fixed (more or less) voltage--And should be OK charging the battery bank (run limited amount of time to charge bank when needed, then you shut it down).

-Bill