I am not able to replicate the frequency distribution you are describing. I will provide more information below, but please email email@example.com directly for more targeted troubleshooting assistance.
Time use variables (like ACT_CAREHH) report the number of minutes a person spent in the activities included in that category over the course of the day; values should range between 0 and 1440 (e.g., persons may spend anywhere between no time and the entire 24 hour time diary in a given activity). I submitted an ATUS extract of all available years of data that includes respondents, non-respondents, and household members; I am seeing values that range between 0 and 1230. There are a large number of missing values; these belong to persons other than the ATUS respondent (e.g., non-respondents and household members of the respondent–neither of these categories will have reported time use information). Similarly, in a handful of custom time use variables I have created in the past, I am only seeing values ranging between 0 and 1440.
If you are working with a hierarchical data extract, there will be two types of records in your file: person records (these will include demographic information, time use variables summarized to the person for each diary day, other person-level indicators) and activity records (these will include activity-specific information like the location and duration of the activity). In a hierarchical file, the person-level variables will not be present on the activity records. However, I would still expect the time use variables to range between 0 and 1440 (this is how they appear in my extracts).
You can view more information about which detailed activity codes are included in a time use variable by clicking on the variable name, and then any hyperlinks for related activities in the subsequent pop-up window (see ACT_CAREHH below for reference).
Main ACT_CAREHH information:
Additional detail about specific activities included in the broader “Caring for and Helping Household Members” activities category: