CHANGING FROM A HONEYWELL ST7100 TO A ST6400C PROGRAMMER
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ABJ
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CHANGING FROM A HONEYWELL ST7100 TO A ST6400C PROGRAMMER

by ABJ » Wed Aug 22, 2007 6:51 pm

FOLLOWING THE INSTRUCTIONS WITH THE NEW UNIT,THE WIRING GOES FROM 8 TERMINALS TO 6 WITH THE OTHER 2 NOT CONNECTED,BUT THE EXISTING ST7100 UNIT HAS BEEN WIRED DIFFERENTLY.
APART FROM THE MAINS FEED,THERE ARE 2 CABLES OF 3 WIRES EACH COMING OUT OF THE UNIT:
1st. CABLE HAS BROWN-EARTH-BLUE...BLUE TO NEUTRAL BLOCK,BROWN TO TERMINAL 6. EARTH TO EARTH BLOCK
2nd.CABLE HAS BROWN-GREEN-EARTH....BROWN TO 5,GREEN TO NEUTRAL BLOCK,EARTH TO EARTH BLOCK.
ALSO,8 IS BRIDGE WIRED TO 3 WHICH IS BRIDGED TO LIVE BLOCK,
AND7 IS BRIDGED TO 5.
6 AND 3 ARE COMMON (H/W AND C/H)
H/W ON IS 8...H/W OFF IS 7.........C/H ON IS 5 ...C/H OFF IS 4.

Hope it is understandable and someone can help..thanx.