22
CD3000S
1PH from 10A to 90A
User’s manual
Heater break alarm and SCR short circuit
Only with HB option
The Heater Break circuit to work properly must have at least an input of 25% of the nominal
current.
H.B. circuit read load current via a current transformer 25-50/0.05 or 100/0.05 depending on thyristor size.
Minimum current is 30% of the current transformer size’s. If load current is below this value make two turns or
more around current transformer. H.B. circuit also diagnoses fuse failure.
7.1 HB alarm contact (only with the HB option)
CD3000S up to 25A is supplied with Heater Break (HB) alarm contacts normally opened (NO) and normally
closed (NC), for the other sizes instead, the contact standard of alarm is normally opened (NO):
• In normal conditions (without alarm) and with auxiliary power supply, the contact to the terminals has opened
(relay coil energized).
• In alarm condition or without auxiliary power supply the contact to the terminals is closed (relay coil not
energized).
If you wish to change the alarm contact put the jumper as shown:
7
JP1
JP
6
JP
2
JP2
JP3
JP6
G1
K1
K2
G2
JP1
JP
3
JP4
CN1
CN2
+
+
+
+
+
-
+
-
JP5
JP4
JP5
K1
K2
G2
JP1
A B C
JP1
C
B
A
35A-45A
60A-90A
Type
JP1
NO (standard)
A-B
NC
B-C
