# How can I address a Siemens S7 DATE\_AND\_TIME OPC Tag

**URL:** <https://forum.inductiveautomation.com/t/how-can-i-address-a-siemens-s7-date-and-time-opc-tag/10040>\
**Category:** Ignition\
**Created:** [May 20, 2015, 3:33pm UTC](https://forum.inductiveautomation.com/t/how-can-i-address-a-siemens-s7-date-and-time-opc-tag/10040 "2015-05-20T15:33:31Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![StudentProject](https://avatars.discourse-cdn.com/v4/letter/s/2acd7d/32.png) [@StudentProject](https://forum.inductiveautomation.com/u/StudentProject)\
**Post date:** [May 20, 2015, 3:33pm UTC](https://forum.inductiveautomation.com/t/how-can-i-address-a-siemens-s7-date-and-time-opc-tag/10040/1 "2015-05-20T15:33:31Z")

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Hi,

the user manual gives information of addressing to S7 items like DInt, Word, Byte… by the OPC-Path “[device\_name]address”.

We can address the DataTypes given in the user manuel, but we want to address a S7 DATE\_AND\_TIME DataType.  
Which Synthax do we need to use to address a S7 DATE\_AND\_TIME DataType in one of our DataBlocks?

At the moment we tried “[device\_name]DBn,B12.6” because the DATA\_AND\_TIME DataType has 6 Bytes, but this did not work.

Thanks.

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**Author:** ![Kevin.Herron](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/kevin.herron/32/7259_2.png) [@Kevin.Herron](https://forum.inductiveautomation.com/u/Kevin.Herron)\
**Post date:** [May 20, 2015, 3:41pm UTC](https://forum.inductiveautomation.com/t/how-can-i-address-a-siemens-s7-date-and-time-opc-tag/10040/2 "2015-05-20T15:41:19Z")

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It looks like we have a long-standing feature request to add DT and DOT datatypes to the driver… ☹

See the work-around in this thread for now: [inductiveautomation.com/forum/v … =72&t=8899](https://inductiveautomation.com/forum/viewtopic.php?f=72&t=8899)

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**Author:** ![Andrew\_Buldyzhov](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/andrew_buldyzhov/32/74246_2.png) [@Andrew\_Buldyzhov](https://forum.inductiveautomation.com/u/Andrew_Buldyzhov)\
**Post date:** [September 24, 2025, 10:32am UTC](https://forum.inductiveautomation.com/t/how-can-i-address-a-siemens-s7-date-and-time-opc-tag/10040/3 "2025-09-24T10:32:15Z")

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S7 Date\_And\_Time type has 8 bytes. Each byte represents year, month, day, hours, minutes, seconds, and milliseconds (two bytes) in BCD format. More details are [here](https://docs.tia.siemens.cloud/r/en-us/v20/data-types/date-and-time/date_and_time-date-and-time-of-day).

The solution is described in [this thread](https://forum.inductiveautomation.com/t/siemens-driver-date-and-time-values/5198/33).