Spectrex 20/20SI Triple IR (IR3) Flame Detector - Manual (Page 37)

Spectrex Inc. - SharpEye TM IR3 Flame Detector Manual – TM 20/20I, Rev. (6) August 2004
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6.7 Terminal wiring (See Fig. No.10 and No.11.)
The detector contains a Terminal Board consisting of two (2) terminal blocks (Item
4). The left terminal block is labeled 1 to 7, the right terminal block is labeled 8 to
14.
The following describes the function of each electrical terminal of the
detector:
• Power Supply (Terminal Numbers 1, 2):
Input power is supplied to Terminal No. 1.
The RETURN is connected to Terminal No. 2.
• Manual Bit Activation (Terminal No. 3):
Terminal No. 3 is used for the Manual BIT activation. The manual BIT is
initiated by a momentary connection of Terminal No. 3 to the power supply
Return line.
Fault Relay
(Terminal Numbers 4, 5):
The Fault output is N.O. SPST relay at Terminals No. 4 and 5. The contacts
are closed when the detector is in its normal operational condition.
• Alarm Relay (Terminal Numbers 6, 7, 8):
The Alarm output is a change over contact relay (SPDT).
Terminal No. 6 is the N.O. relay contact.
Terminal No. 7 is the COMMON relay contact.
Terminal No. 8 is the N.C. relay contact.
• Accessory Relay (Terminal Numbers 9, 10):
The Accessory output is N.O. SPST relay at Terminals No. 9 and 10.
The Accessory relay may act in parallel with the ALARM relay to activate
another external device or it may provide a warning signal, depending on the
position of SW1-2.
Note
To protect the dry contacts from voltage surges when connected to reactive
loads (electric motors, sirens, etc.) connect an appropriate varistor over these
contacts.