"Does my employer have to tell me my Weingarten rights before conducting the meeting or interview?"

No! While many good employers voluntarily honor the Weingarten rights, it is up to employees to know their rights and ask for representation in meetings.

"I have been called to meet with my employer, when and how should I request representation?"

Ask for representation as soon as the meeting is called. However, at any time, even in the middle of a meeting, when you become aware that the employer is trying to obtain information for disciplinary purposes, you can request representation.
You can request your Weingarten rights be honored by simply asking for union representation. The request does not have to be in writing or have any specific wording, simply say, “I would like representation.”
If you have been called into a meeting, and you invoked your Weingarten rights and they were not honored, contact your Executive Board Officers, property shop stewards and the union office at 214-828-1641. ATU 1338 is here to protect your rights to union representation.