ENGLISH
Pag. 3
1. Introduction
The three-relay card (STS3REL) for SMART3/SMART S gas detectors allows the detector to be
provided with tension free changeover contacts.
• The rst output is to be associated to the Fault and Watch-dog alarm
• The second output can be associated to the rst or second alarm threshold
• The third output can be associated to the second or third alarm threshold.
The card comes complete with a at cable and connector to be easily plugged on the detec-
tor’s main board.
When used with the SMART S detector, the function of the relays can be modied by the
detector’s operating menu.
2. Technical specications
Relays contact ratings: 1A a 24 Vdc / 0.5A a 125Vac.
STS3REL board is designed to be installed in systems with a functional safety SIL2. In order
to guarantee this capability the following settings must be implemented
• Relays must be set as normally energized.
• Duringt installation step, connect a 1.33A fuse to each relay’s output.
• Check the relays functionality at least one time per year, by testing detector response
with gas application and checking the relays activation.
The following table describes the STS3REL safety parameters:
PFD λs [1/h] λdd [1/h] λdu [1/h] T1 MTTR
4,36E-05 2,28E-08 0,00E+00 9,90E-09 1 year 24h
3. Layout and conguration
JP9 JP6 JP4
RELÈ 3RELÈ 2
RELÈ 1
DL1 DL3 DL2 DL4 DL5
JP8JP5JP3
6
1
JP2: Connettore relè
COM1
S1
COM2
S2
COM3
S3
1 1 1
1 1
JP2
JP1
JP4: sicurezza relè
Chiuso (default): normalmente non energizzati
Aperto: normalmente energizzati
JP9:
1-2 chiusi: relè 3 su allarme 2
2-3 chiusi (default): relè 3 su allarme 3
JP6:
1-2 chiusi: relè 2 su allarme 1
2-3 chiusi (default): relè 2 su allarme 2
JP3, JP5 e JP8: segnale relè 1, 2 e 3
1-2 chiusi: normalmente chiuso
2-3 chiusi (default): normalmente aperto
JP1: Connettore scheda base
DL1 LED verde - acceso quando scheda alimentata
DL2 LED giallo - acceso quando errore nel watchdog
DL3 LED giallo - acceso quando rilevatore in fault
DL4 LED rosso - acceso per allarme 1 o 2
DL5 LED rosso - acceso per allarme 2 o 3
JP9 JP6 JP4
RELAY
3
RELAY
2
RELAY
1
DL1 DL3 DL2 DL4 DL5
JP8JP5JP3
6
1
JP2: Relays connector
COM1
S1
COM2
S2
COM3
S3
1 1 1
JP2
JP1
JP4: security of relays
Closed (default): normallly not energized
Open: normally energized
JP9:
1-2 closed: relay 3 for alarm 2
2-3 closed (default): relay 3 for alarm 3
JP6:
1-2 closed: relay 2 for alarm 1
2-3 closed (default): relay 2 for alarm 2
JP3, JP5 and JP8: signal of relays 1, 2 and 3
1-2 closed: normally closed
2-3 chiusi (default): normally open
JP1: Main board connector
DL1 green LED - ON when the device is powered ON
DL2 yellow LED - ON when watchdog error
DL3 yellow LED - ON when fault
DL4 red LED - ON when alarm 1 or 2
DL5 red LED - ON when alarm 2 or 3
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