NIB SENTROL ESL 505 CLEAN ME & 2 TO 4 WIRE CONVERTER MODULE FOR 521 SERIES SMOKE

Description

NIB SENTROL ESL 505 CLEAN ME & 2 TO 4 WIRE CONVERTER MODULE FOR 521 SERIES SMOKE
The ESL 505 module serves as an interface between the ESL 521 series low profile self-diagnostic smoke detector and a UL Listed 12/24 VDC control panel.  The 505 is able to interpret the 521 series trouble (CleanMe) signal and provide an output to the control panel via relays.  This signal allows installers to receive a message remotely that the 521 series needs maintenance such as cleaning before a false alarm occurs.  The signal is also provided if the detector has a trouble such as a hardware fault.
Another feature available in the ESL 505 module is the ability to take the 521 two-wire smoke detectors and convert them to a four-wire input on a control panel.  This feature is useful when a panel does not provide inputs for a two-wire smoke detector loop.  The 505 module is UL two-wire compatibility listed with up to 20 of the ESL 521 series smoke detectors.
I owned an alarm company for 35 years and have now sold the business.  This is left-over inventory from the business sale.  I believe I received this module on some type of promotion, since I primarily sold the System Sensor brand of smoke sensors.  The module is absolutely brand new, pristine, never installed, only taken out of box to inspect it and take photos for this eBay sale.