# About isDaylightTime()

**URL:** <https://forum.inductiveautomation.com/t/about-isdaylighttime/88015>\
**Category:** Ignition\
**Tags:** scripting, vision\
**Created:** [March 28, 2024, 6:03am UTC](https://forum.inductiveautomation.com/t/about-isdaylighttime/88015 "2024-03-28T06:03:24Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![Sasi\_Rai](https://avatars.discourse-cdn.com/v4/letter/s/ed655f/32.png) [@Sasi\_Rai](https://forum.inductiveautomation.com/u/Sasi_Rai)\
**Post date:** [March 28, 2024, 6:03am UTC](https://forum.inductiveautomation.com/t/about-isdaylighttime/88015/1 "2024-03-28T06:03:24Z")

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Hi All,

I want to place an indicator on a Vision page to indicate if Daylight Saving Time is on.

In the Script Console, system.date.isDaylightTime() works fine.

I have Boolean Tag called "DST" with value source as expression. For the expression i have system.date.isDaylightTime(now()). This doesn't go down well:

![image](https://us1.discourse-cdn.com/inductiveautomation/original/3X/4/f/4fd0d7b6736741c016858a73889f8ccddacecc0e.png)

I have tried many variety of the expression. Doesn't work. What am I doing wrong here?

Have a wonderful break, All. Thanks.

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**Author:** ![Transistor](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/transistor/32/3380_2.png) [@Transistor](https://forum.inductiveautomation.com/u/Transistor)\
**Post date:** [March 28, 2024, 8:41am UTC](https://forum.inductiveautomation.com/t/about-isdaylighttime/88015/2 "2024-03-28T08:41:17Z")

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`system.date.isDaylightTime(now())` is not an **expression**. It is a **script**.

Expression Language has [dateIsDaylight | Ignition User Manual](https://docs.inductiveautomation.com/docs/8.1/appendix/expression-functions/date-and-time/dateIsDaylight) so try:  
`dateIsDaylight(now())`

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<div class="post-metadata">

**Author:** ![Sasi\_Rai](https://avatars.discourse-cdn.com/v4/letter/s/ed655f/32.png) [@Sasi\_Rai](https://forum.inductiveautomation.com/u/Sasi_Rai)\
**Post date:** [March 29, 2024, 7:01am UTC](https://forum.inductiveautomation.com/t/about-isdaylighttime/88015/3 "2024-03-29T07:01:31Z")

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Thanks Transistor. Works perfectly. Understood why I was getting the error.