User manual - RATEMETER STI-73
Depending on version:
85...
230
...260V AC/DC or
19...
24
...50V DC; 16...
24
...35V AC
Figure 4.7. Connection of power supply and relays
Contacts of relay outputs are not equipped with spark suppressors. While use
the relay outputs for switching of inductive loads (coils, contactors, power
relays, electromagnets, motors etc.) it is required to use additional
suppression circuit (typically capacitor 47nF/ min. 250VAC in series with
100R/5W resistor), connected in parallel to relay terminals or (better) directly
on the load. In consequence of using the suppression circuit, the level of
generated electromagnetic disturbances is lower, and the life of relay contacts
rises.
a)
b)
Figure 4.8. Examples of suppression circuit connection:
a) to relay terminals; b) to the inductive load
11
!
!
N
3 4
3 4
L
L
N
!
FUSE
1
2
L N
L N
3 4
FUSE
R1
