Appliance Description; Display; Keypad; In-Line Switch Strip/Potentiometer - Hengstler signo 721 Benutzerhandbuch

4. Appliance description

Note
This chapter explains the functions of
• the display
• the LED indicators
• the keys
• the switches
• the potentiometer and
• the connection terminals.
These descriptions are compiled to include the sometimes varying
functions of all counter versions.
Please read this chapter carefully because it will provide you with the
information required to adjust and connect your counter by means of
the switches, the potentiometers and the external connections for the
special requirements of its further application.
P
signo 721
Preset counter
counter
1 Display, 5 digits (line 1)
2 LED indicators (line 2)

3 Keypad

4 In-line switch strip
5 Potentiometer
6 Connection terminals 1- 8 (plug-in type)
7 Connection terminals 9 - 16 (plug-in type)
8 Type plate
Fig. 4-1 Preset counter signo 721 with one and 2 presets
front/rear view

4.1 Display

P COR PSC
Line 1
Line 1 comprises a 5-digit numerical display which shows the current
count during counting operation.
During programming, the preset value, correction value and prescaler
value are indicated in this line.
Line 2
In Line 2, LED indicators show the menu item selected.
16/24
P 2
signo 721
Preset
P 2
Line 1
Line 2
P1 P2 COR
4.2 Keypad
E
Programming and inquiry of numerical values as well as the manual
reset are carried out by means of four keys on the front of the
counter.
With this key all numerical values can be accessed.
Programmed values may be inquired or modified. The menu
E
items are selected in rotation from the left to the right.
This key is only operative during programming mode, as long
as any of the indicators in line 2 light up. With this key the
digit in line 1 to be modified is selected. The digits are
selected from right to left.
This key has 2 functions.
1. In programming mode it is used to set the required value
for the selected digit. Each time the key is pressed, the
value of the digit will be increased by one.
2. In order to reset the counter with the keypad, this key
must be pressed together with key "R".
In order to reset the counter with the keypad, this key must
be pressed together with key
R

4.3 In-line switch strip/potentiometer

Reset 9
Auto-Reset On 8
Keyl1 Off 7
Keyl2 Off 6
Key-Reset Lock 5
Input 5 kHz 4
Display-Hold Off 3
Inhibit Off 2
pnp-Input 1
0,05 s
Out 2 1 s
bist.

4.3.1 Functions of switches and potentiometer

Switch 1
pnp/npn input (pnp-lnput/npn)
For actuation of count and control
inputs (terminals 11-14) with an
external
• pnp circuit
(active edge from low to high)
• npn circuit
(active edge from high to low ).
PSC
Switch 2
Gate (Inhibit Off/On)
The switch position defines whether the count input (terminal 11)
can be inhibited by feeding a high potential to the application input
(terminal 13).
This gate function allows the counting process to be interrupted
specifically in case of continuous counting pulses.
Switch 3
Display memory (Display-Hold Off/On)
(only in versions ...101 to ... 110)
The position of this switch defines whether the display can be "frozen"
or not be feeding a high potential to the application input (terminal
13).
R
.
Set
Off
On
On
On
0 721 121/122/125/126
30 Hz
On
On Switches 2 and 3 have no function
npn
in the up/down version.
0 721 121/122/125/126
In above counters the switch
positions npn and pnp are sub-
tracted in case of a low signal
at the application input (termi-
nal 13) and added in case of a
high signal.
Sach-Nr. 2 721 091; Version 1250100MW