Change Over Relay

Seeking help
1 x blind installed with its own in built adjustable limit switches
1 x 2 key saturn switch (1 button up, 1 button down)
1 x changeover relay, using one channel (the other 3 are for future blinds)

The blind is 240V so I have used the N/O contacts for up, and N/C for down or vice versa. At the blind I have 2 actives, 1 neutral, 1 earth.

What is the best key functions to make the blind go all up, or all down. Client is not interested in stopping half way. Should they be on a timer or a scene.

So far I am confident in basic programming.

 

they cant be on a timer, because as soon as the timer expires it will turn "off" thus driving the blind in the opposite direction.

Using one change over relay gives you no un-powered state, it will either be always driven up and driven down, and only the limit switches will stop it. Is the blind designed to take power 24/7? (I dont know about blinds so I am just asking questions).

how do you prevent the owner from reversing the direction instantly - cant be done with one change over relay.

Good interlocking can be achieved with two changeover relays and this also offers an off state. Software can then add a delay between change of direction.

As for key function, one key as an On (Up) and the Other as an Off (Down).

Mick

 

Iam told that the blinds can have constant power (manufacturer has informed me that the same blinds, in same situation have been installed at numerous jobs, he knows nothing about programming them).
As far as I can make out
1 x button up
1 x button down
constant power with only the limit switches to stop the motion
based on this information what would you suggest to be the best key functions?
Thanks in advance

 

The LED will be on when the up is pressed.

If you want to off to be on when down then you may need to use the ramp function (at a guess). Start simple and work from there

 

Read this Clipsal whitepaper for suggested motorised device installations -

http://www.cbusforums.com/forums/showthread.php?t=3276

 

Motor requirements

Unfortunately, the whitepaper only shows how to avoid damage to the Clipsal relais, nothing mentioned there about the damage you can do to the attached motors if controlled incorrectly by C-bus relais.

99% of all tubular motors on the market (used for Roller blinds, Roller shutters, Awnings, etc) as well as Venetian Blind (or JA or Square motors) have the following requirements if they are AC (240V) controlled:

1:
Do not wire in parallel unless specifically allowed by the manufacturer (and if: watch for the switching capacity: Motor can take up to 2 times their nominal current during start-up (0.05 - 0.2 sec depending on size)

2:
Never activate up and down at the same time (No other way to burn out a motor faster )



3:
Allow for a switch-over delay between up and down of at least 0.5 sec. (Connecting the motor on one changeover relay using the NC and NO contacts for up and down WILL damage the motor over time, unless the motor is ALWAYS run completely up or down before switching directions. Also: By doing so, there is no stop halfway...)


There are a number of possible solutions, including 3rd party controllers, refer to the following treads:


http://www.cbusforums.com/forums/showthread.php?t=97
(A very good tread, have a look at Post 29 and 31, it is actually from Clipsal staff in Sydney)

http://www.cbusforums.com/forums/showthread.php?t=1008

there is plenty more out on the forum, just search for "Roller blind" or "Shutter"

Hope this helps (to avoid future damge)