Alarm Timing

Come here to introduce yourself, who you are, and what you do
Post Reply
Mtak
User
User
Posts: 2
Joined: Thu Sep 23, 2021 1:32 am

Alarm Timing

Post by Mtak »

Hi All,
We have recently purchased an ADC 24 and are using Picolog 6 on a Windows 10 platform. We have previously had an ADC 20 which we have used without issue.
We have 2 channels set up with 100ms sample rate and functioning correctly (the final intention is to use 15 channels) and have been monitoring the alarms and outputs driven by the alarms.
We noticed that with a 0 second "delay on" to 2 second "delay on" the alarm (basic max and min limits) and corresponding output take approximately 3 seconds to operate.
Is this normal?
Is there a way to get the alarm / output to operate at the sample rate or close to the sample rate in the picolog 6 software?
Does it require the use of the SDK to develop specific code to drive the alarm / output at sample rates under 1 second.
Any assistance in resolving this would be appreciated
Regards
Mark

Gerry
PICO STAFF
PICO STAFF
Posts: 1034
Joined: Mon Aug 11, 2014 11:14 am

Re: Alarm Timing

Post by Gerry »

High Mtak,

In the SDK, you would just set the Digital Outputs in response to analyzing the data (for your PicoLog 6 alarm condition). So, the rate at which you could change the Digital Outputs would depend upon, the conversion time, the time to check if the data meets your alarm condition and then set the Digital outputs, and the time to establish a connection over USB along with the time for the ADC-24 to respond to the command. Aside from the Time to convert the data, the time to establish the USB connection would likely be the next longest time (which could be 10's of milliseconds or longer).

So, it could be possible to get the outputs toggling at less than 200ms for a conversion time of 100ms (but this would need to be tested) but the real issue may be that the time to establish a connection may vary by 10's of milliseconds, which means that the frequency at which the digital outputs switch would vary.

Why do you need a closed loop system based upon Conversions, Alarms and Digital outputs, i.e. what is it that you are trying to achieve?

Regards,

Gerry
Gerry
Technical Specialist

Mtak
User
User
Posts: 2
Joined: Thu Sep 23, 2021 1:32 am

Re: Alarm Timing

Post by Mtak »

Hi Gerry,
Is there an option in the Picolog 6 software to increase the alarm activation speed?
The need for a closed loop system is to provide basic control for "equipment protection" during testing and data logging. The preference is not to have to use the SDK to develop code but to use the Picolog 6 software. Activation of alarm in 500ms to 1s would be acceptable. I can provide some plots, config files and details of the test setup to help resolve this issue.
Kind Regards
Mark

Post Reply