Re: Urgent help required: Star vs Daisy chain wiring for aircon control

["Frank Mc Alinden" <frankmc@xxxxxxxxxxxxxxxx>]

Have you got a link to a website with the docs on it for the  stats ??

Frank

----- Original Message -----
From: "christopher purves" <CHRIS_PURVES@xxxxxxx>
To: <ukha_d@xxxxxxx>
Sent: Wednesday, September 28, 2005 10:17 PM
Subject: Re: [ukha_d] Urgent help required: Star vs Daisy chain wiring for
aircon control


>
> I wish I could find out - I am digging in their docs.
>
>
> Chris
>
>
>>From: "Frank Mc Alinden" <frankmc@xxxxxxx>
>>Reply-To: ukha_d@xxxxxxx
>>To: <ukha_d@xxxxxxx>
>>Subject: Re: [ukha_d] Urgent help required: Star vs Daisy chain
wiring for
>>aircon control am I screwed
>>Date: Wed, 28 Sep 2005 22:12:52 +1000
>>
>>Hi Chris
>>             Can you confirm  that the communication is rs 485
???....If
>> so
>>then it  should be ok to star or daisy chain ,although rs485 specs
state
>>daisy chaining......
>>
>>Frank
>>----- Original Message -----
>>From: "christopher purves" <CHRIS_PURVES@xxxxxxx>
>>To: <ukha_d@xxxxxxx>
>>Sent: Wednesday, September 28, 2005 10:07 PM
>>Subject: [ukha_d] Urgent help required: Star vs Daisy chain wiring
for
>>aircon control am I screwed
>>
>>
>> > OK the story so far:
>> >
>> > We have had a whole house Daikin air conditioning system
installed(hot
>>and
>> > cold). 8 indoor units connected to 2 external units (4
internals to
>> > each
>> > external). We opted for a touchscreen to control this setup
as it could
>> > provide timing to turn units on and off along with themostats
and so
>>forth
>> > so it behaved much like a convetional heating system.
>> >
>> > Each unit in the chain (including external units and the
touchscreen)
>>has
>> > an
>> > f1 and f2 signal connection.
>> >
>> > Originally Daikin told our installer to wire as a 'star' back
to the
>> > touchscreen location which required a single 2 core cable to
each
>> > indoor
>> > and
>> > outdoor unit back to the touchscreen which of course they
did. In
>> > effect
>> > join all f1's together and all f2's together and attach to f1
and f2 on
>> > the
>> > trouchscreen.
>> >
>> > However when speaking to Daikin today, Daikin are claiming
the internal
>> > units must be wired in a daisy chain (one to the next). 4
units daisy
>> > chained into 1 external unit (so 2 setups like that) and then
both
>> > external
>> > units back to the touchscreen (again f1's to f1's, f2's to
f2's).
>>Clearly
>> > the existing wiring does not support this method as there are
not
>> > enough
>> > cores but, I cannot for the life of me understand why a star
and a
>> > daisy
>> > chain should be any differrent ? Electrically it seems the
connections
>>are
>> > the same.
>> >
>> > I would also point out that each unit has an address settable
by a four
>> > input dip switch.
>> >
>> > Can we just ignore their comments and wire it a as a star ?
>> >
>> > Certainly CBUS can be wired as either.
>> >
>> > Anyone ?
>> >
>> > Help greatly appreciated. The installer and I are tempted
just to try
>> > it
>> > but
>> > given the cost of the equipment we are a little nervous. On
the
>>otherhand
>> > given that all the decoration is now finished it will cost us
thousands
>>to
>> > rewire.
>> >
>> > Ta
>> > Chris
>> >
>> >
>> >
>> >
>> >
>> >
>> > Yahoo! Groups Links
>> >
>> >
>> >
>> >
>> >
>> >
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>>
>>Yahoo! Groups Links
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> Yahoo! Groups Links
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