Limits and capacities

The limits below are built into YTCC. A limit marked as a setting can be changed; the page linked in the row says where. MB and MiB in this table mean 1024 × 1024 bytes.

Projects and packages

Limit	Value	Applies to	When exceeded
Project name	51 characters; lowercase letters, digits and _, starting with a letter	New Project	At most 51 characters
Project title	80 characters	New Project, project details	Title can be at most 80 characters
Project description	500 characters	New Project, project details	Description can be at most 500 characters
Screen package, total	200 MB	Import a screen package	Zip file too large; at most: 200 MB; after unpacking Package too large when extracted; at most: 200 MB; for a folder Folder too large; at most: 200 MB
Screen package, one file	25 MB	Each file in a screen package	File too large; per-file limit: 25 MB with the file name and size
Uploaded file (image or other asset)	25 MB	Files uploaded to a project	The server refuses the file.
Project package import	2048 MB (setting on the projects server)	Import a project package from the home page	The server refuses the package
Home page backups kept on the server	10 per project (setting backup_exports_keep, 1 to 1000)	Back up a project from the home page	After each new backup, the oldest copies of that project are deleted; downloaded files are not affected

Configuration editor

Limit	Value	Applies to	When exceeded
XLSX import file	64 MiB	Import and export with Excel or CSV	Request/file exceeds the size limit (64 MiB)
CSV import file	1 GiB (setting on the server)	Same	The server refuses the file
One CSV record	1 MiB (setting on the server)	Same	The import stops with an error naming the line
XLSX export sheet	1,000,000 rows	Export	Not a limit on the data: further rows continue on the next sheet
Clone	1000 copies	Clone… in the signal grid (Edit signals in the grid)	The number is set back to 1000
Internal signal expression	4096 characters, 64 input signals, 32 nested levels, depth 64	Expression syntax	Validation reports an expression error
Alarm levels	32 per signal, the four fixed levels included	Define alarms	At most 32 levels

Runtime screen

Limit	Value	Applies to	When exceeded
Trend signals	8	Use the trend	At most 8 signals in a trend; the search box is disabled
Trend axes	4	Same	No message: signals with further units share the last axis
Signal details panels	4 open at the same time	Look at the details of a signal	The oldest panel closes
Live signals of hidden pages	20,000 (project setting Hidden page live tag limit)	Page cache and screen subscription	No message: the page hidden longest stops receiving values and briefly shows old values when it is shown again
Live signals per browser connection	200,000 (server setting ws_max_subscriptions)	Every screen	A banner says how many signals cannot be shown (server subscription limit ws_max_subscriptions).
Command reason	500 characters	Commands and confirmation	The field accepts no more characters
Second-user approval	5 minutes, used once	Critical commands and interlock overrides	The approval expires; approve again

Alarms, events and history

Limit	Value	Applies to	When exceeded
Alarm list scope: areas	64	Scope field of alarm and event lists	Max 64; the event list shows Too many areas selected
Alarm list scope: path patterns	32, each up to 256 characters	Same	Max 32
Alarm history period	366 days	Search and export the alarm history	Invalid filter: start must be before end, range at most 366 days
Event list search and count	31 days	What the event list records	Time range for search and count can be at most 31 days
Event list search text	128 characters	Same	Search text too long (max 128 characters)
Excel and CSV export	1,000,000 rows	Export data: event list, alarm list, alarm history, command log, signal list	The file ends with a line saying that the limit was reached; narrow the filter
History readout	2000 intervals	Trends and history queries	The interval is made larger

Users and sessions

Limit	Value	Applies to	When exceeded
Failed sign-in attempts	5 in a row, then locked for 15 minutes (project settings)	Password and lockout policy	Too many failed attempts. Account locked., then Account locked. Try again in {0} minutes.
Idle session	30 minutes, warning 60 seconds before (project settings)	Sessions	The session ends

Electrical diagrams and maps

Limit	Value	Applies to	When exceeded
SCL file	64 MB	Import a single-line diagram from IEC 61850 SCL	File is too large (over 64 MB).
SVG file of a user symbol	512 KB, 2000 elements	User-defined electrical symbols	File too large (512 KB at most); too many elements is reported
GeoJSON layer of a map	20 MB, 5000 features, 2000 points per feature	Map object	Features with more points are simplified