Hach-Lange SI628 C - Manual (Page 17)

13
3. Installation
ENGLISH
3.4. Protective wiring of switching contacts
Relay contacts are subjected to electrical erosion.
Especially with inductive and capacitive loads, the service life of the contacts will be reduced.
For suppression of sparks and arcing, components such as RC combinations, nonlinear resistors, series
resistors and diodes should be used.
Important note:
Fit a jumper between terminals 9 and 10 (12 and 13 in panel mount instrument) and another between
the terminals 11 and 12 (10 and 11 in panel mount instrument).
3.3.2. Cells with connector S8
Typical protective wirings
AC applications with inductive load
DC applications with
inductive load
AC/DC with
capacitive load
Load
Contact
relay
Diode
1N4007
Typical RC at 230 VAC: Capacitor 0.1 µF/630 V
Resistor 100 Ω/1 W
RC
RC
R
Load
R, for example:
5 Ω / 1 W at
24 V / 0.4 A
Maximum relays load: AC < 24 V / < 3 A / < 72 VA.
TERMINALS
COLOUR
si628 C
(wall mount)
si628 C
(panel mount)
9 13 Middle
10 12 Middle
11 11 Shield
12 10 Shield
si628 C_HACH LANGE_Ed. 0510.indd ANG:13 si628 C_HACH LANGE_Ed. 0510.indd ANG:13 20/5/10 11:08:43 20/5/10 11:08:43