Yokogawa chart recorder questions

Hi all,

My team and I are potentially looking to purchase a set of yokogawa DX1000/2000 recorders for our validation work to replace our Kaye validators.

However, there are some things that we can’t quite figure out on our demo unit and I was wondering if any of you could help?

I’m looking to make a math channel setting that causes a message to be output at the start and end of my sterilisation exposure criteria (between 122C and 136C)

Currently I’ve got it set up so it enters alarm mode when the first TC hits 122, and then outputting message 1 when this happens, but this isn’t quite what I’m after- I need it to occur when the last TC hits 122.
I’ve also worked out how to get it to trigger when single TC has its minimum value reach 122 (eg 001.GE.K1 with K1 set as 122), then use the AND function to join these up. However, I’m loath to have to set this up for up to 30 thermocouples every time we validate a new system, not to mention the ugliness and error proneness of such a longwinded way!

So is there a neater way of doing this please? Such as saying (in rather ugly pseudocode) IF (min(Group1)>122) THEN TriggerEventStart (output message 1); ELSEIF (min(Group1)<122) THEN TriggerEventEnd (output message 2)

Thanks for your help,


Found a solution. If anyone else needs it, here is how:
To log the lowest reading channel do the following
• Set the alarm hysteresis value (in Basic Settings mode>Alarm) to 0.0
• Also set Alarm action “No Logging” to ON
• Select a maths channel e.g. CH101 and enable
• Add the maths expression CLOG.MIN(aa-bb) where aa is the lowest channel number and bb is the highest to capture the range e.g. CLOG.MIN(01-12)
• Set an alarm type H (high) against the channel at the desired value e.g. 121.0 degrees C and allocate to S01 (internal switch 1) and Detect = ON
• Set a second alarm type L (Low) against the channel at the same value e.g. 121 degrees C and allocate to S02 and Detect = OFF (this will not register as an alarm event but will trigger the internal switch)
• In General Settings>Event Action, set an event type Switch, No 1, Action = Message 1, and a second event type Switch, No 2, Action = Message 2
• In General Settings>Message set Message 1 to read something similar to “All probes at temperature” and Message 2 to read something similar to “Cycle complete” or whatever you prefer to denote start and end of steriliser cycle