Advice/help required for a "change over " system In a Comms room

[lees8110]

Hi all, I am trying to come up with some sort of "change over" unit for a Comms room.

I have two seperate wall mount mitsubishi split systems both serving the same small area. There is only a need to run 1 unit at one time to cool the area, the second just there for back up (critical Comms equipment). Idealy I want to alternate them on a weekly basis, and have the second come in when the temp rises above the set point in high temperatures or if the current unit goes into fault.

I am aware the par 31 is capable of managing this, but these units are 8 years old and the software is not compatable.

I think mitsu supply a stand alone panel that will do all this and more, but it's very expensive. So I'm hoping there is an alternate solution.

[install monkey]

stick a room stat to switch the live s1 to indoor if temp reaches above 23 deg so you have a run/stand by-but 1 unit would run constantly

[Magoo]

As per IM, and add one of those relays that is powered both ways and a 7 day time clock to switch lead lag arrangement.

[JP6]

We use the Mitsi Procon RS panel and A1M interfaces to do this, but like you say it's an expensive way of doing it.

[r.bartlett]

Contact Sarum they do these

http://www.sarumelectronics.co.uk/

http://www.sarumelectronics.co.uk/duty-share-control-panel.php

[Grizzly]

Contact Sarum they do these

http://www.sarumelectronics.co.uk/

http://www.sarumelectronics.co.uk/duty-share-control-panel.php

Good post RB Thanks I have saved them for future reference.
Grizzly

[JP6]

Contact Sarum they do these

http://www.sarumelectronics.co.uk/

http://www.sarumelectronics.co.uk/duty-share-control-panel.php

What sort of price are these compared to a Procon?

[r.bartlett]

you want me to wipe your a*se as well?

[fred]

can I ask question about refrigerator?

[JP6]

can I ask question about refrigerator?

I wouldn't, r.bartlett might have a hissy fit again :rolleyes:

[lees8110]

I looked at something similar to these where a company will build a panel to suit
your requirements, but it worked out similar costs to the pro con rsns

Good pieces of kit tho if the customer is willing to pay

[lees8110]

stick a room stat to switch the live s1 to indoor if temp reaches above 23 deg so you have a run/stand by-but 1 unit would run constantly

Thanks for your input, isnt S1 the Comms to the outdoor?

[JP6]

S1 live, S2 neutral, S3 is comms. Switching S1 will cut power to the indoor unit, causing it to switch off.