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1-2
Section
Comparison between NT20S and NT21
4
1-2
Comparison between NT20S and NT21
Item
NT20S
NT21
NT Support Tool used
NT
-
ZJCAT1
-
EV4 or NT
-
ZA3AT-EV2
NT-ZJCAT1
-
EV4.6
Effective display area
112 x 56 mm (horizontal x vertical)
117 x 63 mm (horizontal x vertical)
Number of screen dots (resolution)
256 x 128 dots (horizontal x vertical)
260 x 140 dots (horizontal x vertical)
Number of touch switches
12 x 6 dots (horizontal x vertical)
13 x 7 dots (horizontal x vertical)
DIP switch settings
On rear of Unit
None (software settings)
Use of Memory Unit
Not possible
Possible (to transfer system program
data and screen data)
RS
-
232C interface
Connector (9-pin) also used as port for
screen data transfer
- Port A connector (also used for
screen data transfer, 9-pin)
- Port B connector (for host
communications only, 9-pin)
Backlight life
10,000 h min.
50,000 h min.
Replacement backlight
NT20S
-
CFL01
Not replaceable.
Battery backup
Not possible
Possible
*1
(numeral/character string memory
tables, history data, recipe data, and
clock data)
System program data
Pre-installed (cannot be changed)
The system installer and system pro-
gram data are transferred from the NT
Support Tool.
1:N NT Links
Standard
Standard or high-speed
Memory Links
Not possible*2
Possible
Number of user
-
registered screens
Maximum of 500
Maximum of 3999
Screen data capacity*3
(User program memory)
96 KB
512 KB
Numeral and character string
memory tables
Maximum of 128 entries
Maximum of 2,000 entries
Bit memory table
None
Maximum of 1000 bits
Mathematical table
None
256 entries max.
Calculations can be executed
automatically in the PT.
Image data
None
Maximum of 4,095 (224 in
NT20S-compatible mode)
Library data
None
Maximum of 12,288 (896 in
NT20S-compatible mode)
Fixed graphics (rectangles, poly-
gons, arcs, sectors, tiling)
None
65,535 per screen including all fixed
display elements
Image library display
None
256 per screen max.
Analog meters
None
50 per screen max.
Trend graphs
None
1 per screen max.
Broken-line graphs
None
1 per screen max.
Alarm list/history
None
4 per screen max.
Recipes
None
1 per screen max.
Windows
None
Maximum of 3
Method for storing numeric values
(numeral memory data and PT Sta-
tus Control Area)
Fixed as BCD (binary coded decimal)
Selectable from BCD (binary coded
decimal) or binary
PT Status Control Area size
4 words
5 words (partial change of contents) (4
words in NT20S-compatible mode)