Help on finding total hours in military time

Hello all. I have a user input 2 times per day, just the hour, (EX: 12 am or pm, 4 am or pm) I need help determining the total hours. For example: if a user enters 10 am, and 7 am, I need to determine 21 hours. Has anybody ever had to code something like this?

Platform: RS5000

Regards,

JF

It's the normal 24 hour clock to everyone outside of the US.

An yes, I've got some sample code for that. Let me dig it out

That´s elapsed time go to:
http://search.rockwellautomation.co...1&wc=200&wc_mc=1&ud=1&filter=0&q=elapsed time

Then download either AOI or sample program.

snakes79 said:

Hello all. I have a user input 2 times per day, just the hour, (EX: 12 am or pm, 4 am or pm) I need help determining the total hours. For example: if a user enters 10 am, and 7 am, I need to determine 21 hours. Has anybody ever had to code something like this?

Platform: RS5000

Regards,

JF

Click to expand...

It is simple comparing

Easier if you change time values to 24hour format for calculation.
start_time: time 0..12 am or pm
stop time: time 0..12 am or pm
am_pm_start_sel: false = am, true = pm selected
am_pm_stop_sel: false = am, true = pm selected


if start time and am_pm_start_sel=false then
start time_temp:=start_time
end_if

if start time and am_pm_start_sel=true then
start time_temp:=start_time+12
end_if

if stop time and am_pm_start_sel=false then
stop time_temp:=stop_time
end_if

if stop time and am_pm_start_sel=true then
stop time_temp:=stop_time+12
end_if


if start_time_temp>stop_time_temp then
time_dif:=(24-start_time_temp)-stop_time_temp
end_if


if start_time_temp<=stop_time_temp then
time_dif:=stop_time_temp-start_time_temp
end_if

If he is logging on a windows pc....why not just change time format on pc to 24 hours?

I do not understand why the automation world does not standardize on 24 hour time, FAR easier to handle with data.

Lare said:

Easier if you change time values to 24hour format for calculation.

Click to expand...

And with modulo operation even easier (and better to optimize without branches):

time_dif := (24 + start_time_temp - stop_time_temp) MOD 24;

I am not sure how you are getting the user input. But I am assuming FactoryTalk HMI. If so:

I would use a control list selector in on HMI with 24 states to select time. That way when the user selects 7pm the value =19 7am the value = 7

If Start Time >= Stop Time



If Start Time <= Stop Time

widelto said:

That´s elapsed time go to:
http://search.rockwellautomation.co...1&wc=200&wc_mc=1&ud=1&filter=0&q=elapsed time

Then download either AOI or sample program.

Click to expand...

The AOI's work great. Just used it to determine if the barcode date of product is within +/- 8 hours of the current time, if not it gets kick out.