MX 60 for wind [RE-wrenches]
Jeff Clearwater
clrwater at earthlink.net
Mon Aug 2 13:20:21 PDT 2004
<x-flowed>
Your free subscription is supported by today's sponsor:
-------------------------------------------------------------------
Save up to 67% on Omaha Steaks + Get 6 FREE Burgers and a
FREE Cutlery Set + Cutting Board!
http://click.topica.com/caacvgpbz8Qcsbz9JC9a/OmahaSteaks
-------------------------------------------------------------------
Hi Wrenches,
In my search for diversion controls for
wind/solar systems (to replace the EZwire center
for a 175 with a better alternative) I came
across this at
http://www.flexcharge.com/flexcharge_usa/charge_method/flexcharge_charge_method.htm
Anyone have experience with flexcharge contollers? They claim the following.
"There has been allot of discussion over which
charge process is better, PWM, or this method.
To add fuel to the fire, each company making
"ON-OFF" controllers has chosen different
voltages to set the disconnect and reconnect
points. We have seen controllers using a version
of this method where the reconnect voltage on a
12V system was set at 12.6V @ 70°F. On this
system the batteries would never see more than
80% charge, and likely much less. The PWM type
controllers will obviously regulate the charging
your batteries, and with proper temperature
compensation, heat sinks, and the correct
Bulk-Regulate-Float (3 stage) algorithm will do a
pretty good job of it, but why settle when you
can get so much more in a charge regulator.
Instead of three stages with PWM you get an
infinitely variable charge process which will
supply the battery with exactly what it needs and
only when it needs it. You get less plate
saturation gassing, non destructive equalization
and Zero EMI as well. "
Is this just an attempt to have an on-off
controller look good - an attempt to cover up the
basic limitation of on-off controllers?
Ironically they claim it to be an "infinitely
variable charge process? - doesn't full current
pulsing cause plate weakening? They don't say
how long those pulses are. Are we talking
miliseconds or seconds or minutes?
I guess I'm revealing my lack of sophisticated
electronics knowledge here, but when a PWM charge
control is used in a diversion mode, does the
current flow through the controller or is the
controller just acting as a fast switching driver
for a contactor or solid state FET? Can
contactor's handle high speed switching without
burning out? In which case you use a FET, but
why can't the FET's in the conroller be used? Is
that what a C40 is doing in diversion mode?
Isn't that what an Enermaxer was?
When Chris F says the MX60 in conjuction with a
solid state relay can act as a diversion charger
is it using a PWM routine and/or MTTP 3 stage
charging routine? Or is it simply a voltage
sense for an on-off device with a fixed
hysteresis?
Any clarity here would be appreciated.
Thanks!
Jeff
>------------------------------------------------------------------
>
>Jeff Clearwater, Village Power Design wrote:
>> But I remember a conversation with Chris F. at EO
>> a few years back where it seemed like the MX60
>> could be set up in a diversion mode. I also
>> have 35 amps of PV to regulate too however. I
>> could put the PVs on a MX60 and then the wind
>> would be covered
>
>The MX60 can be used to provide control of a diversion load - either AC
>or DC loads can controlled. You need to add the diversion control
>device - either a normal relay or (preferably) a solid state relay. The
>MX60 provides a 12vdc output signal to power the relay's coil - so you
>don't need anything other than a typical 12 vdc coil type relay even if
>the system is 24 or 48 vdc nominal.
>
>Solid state type relays can be switched much faster than mechanical
>relays - so the "smoothness" of the diversion control is better (i.e.
>the power is PWM'd). When using solid state relays you need to set the
>on/off time delays in the MX60's diversion system setpoints to zero.
>Solid state relays can be ordered for either AC or DC loads and need to
>be mounted on a heatsink. I usually suggest the Eurotherm / continental
>brand of solid state relays -
>http://www.ciicontrols.com/products/svdd.htm - which will handle up to
>100 vdc and 40 amps per device (you can have more than one controlled by
>a MX60 for larger systems).
>
>The OutBack FX inverter can also provide a diversion output control
>signal (it also is a 12vdc signal). It also has an AC diversion mode
>setting in which the diversion load is turned off if the inverter gets
>too hot or hits its overload limits. This was suggested by Bob-O of
>Electron Connection as he was using the FX to dump hydro output to his
>electric water heater and had an issue when the well pump would start,
>causing the inverter to current limit and flicker the output
>momentarily. With the new AC diversion mode, the dump load would be
>turned off instantly when the motor started - eliminating the flicker.
>
>
>Christopher Freitas
>OutBack Power Systems, Inc.
>cfreitas @ outbackpower.com
>www.outbackpower.com
>Arlington WA USA
>Tel 360 435 6030
>
>Your free subscription is supported by today's sponsor:
>-------------------------------------------------------------------
>Get a Great Credit Card for You Today
>You can find a credit card to fit your credit needs.
>All types of credit cards -- 0% APRs, Rewards, & Bad Credit.
>http://click.topica.com/caacpgdbz8Qcsa9hBZif/411Web
>-------------------------------------------------------------------
>
>- - - -
>To send a message: RE-wrenches at topica.com
>
>Archive of previous messages: http://lists.topica.com/lists/RE-wrenches/read
>
>List rules & etiquette: www.mrsharkey.com/wrenches/etiquete.htm
>
>Check out participant bios: www.mrsharkey.com/wrenches/
>
>Hosted by Home Power magazine
>
>Moderator: michael.welch at homepower.com
--
~~~~~~~~~~~~~
Jeff Clearwater
Village Power Design Associates
Sustainable Energy & Water Solutions for Home & Village
http://www.villagepower.com
gosolar at villagepower.com
877-SOLARVillage
425 Nimrod St.
Nevada City, CA 95959
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~`~
--
[Non-text portions of this message have been removed]
Your free subscription is supported by today's sponsor:
-------------------------------------------------------------------
Get a Great Credit Card for You Today
You can find a credit card to fit your credit needs.
All types of credit cards -- 0% APRs, Rewards, & Bad Credit.
http://click.topica.com/caacvgubz8Qcsbz9JC9f/411Web
-------------------------------------------------------------------
- - - -
To send a message: RE-wrenches at topica.com
Archive of previous messages: http://lists.topica.com/lists/RE-wrenches/read
List rules & etiquette: www.mrsharkey.com/wrenches/etiquete.htm
Check out participant bios: www.mrsharkey.com/wrenches/
Hosted by Home Power magazine
Moderator: michael.welch at homepower.com
--^----------------------------------------------------------------
This email was sent to: michael.welch at homepower.com
EASY UNSUBSCRIBE click here: http://topica.com/u/?bz8Qcs.bz9JC9.bWljaGFl
Or send an email to: RE-wrenches-unsubscribe at topica.com
For Topica's complete suite of email marketing solutions visit:
http://www.topica.com/?p=TEXFOOTER
--^----------------------------------------------------------------
</x-flowed>
More information about the RE-wrenches
mailing list