Update: Traced this to the Freqrol FR-SFJ spindle controller which was on life support. Would never have guessed this from the symptoms.
My 4400 drops into alarm mode as soon as I power up the controller. Screen reads :
<NC ALARM> ALARM DIAGN 1
S04 AMP CONNECT OFF
Y04 AMP UNEQUIPPPED
<STOP CODE>
<ALARM MESSAGE>
<OPERATOR MESSAGE>
I thought I had isolated it to the valve which controls the clamp/unclamp cylinder. Replaced the valve (actually had to scab a new valve in, as the OEM Taiyo valves are no longer available in the US) and the problem went away, only to recur on the next start up. I can't really make heads of tails or the O&M manual with regard to alarms and troubleshooting.
I'd really appreciate suggestions, as I'm desperate to get this machine back up and running.
Update: Traced this to the Freqrol FR-SFJ spindle controller which was on life support. Would never have guessed this from the symptoms.
I have an old Frequol drive of unknown type and condition at home (I'm not there now)). Email me if you'd like to explore the unlikely possibility that is the same model number as yours.
Mike