Delta Controls ADM-2W704 - Page 18

Access Door Module ADM-2W704 (Rev 1.3) Installation & Application Guide
Page 18 of 26 Access Door Module
Type 3 EOL Circuit (Normally Closed Contact)
This EOL Circuit is used to monitor/supervise a Normally Closed contact, to indicate Trouble when there is
either a Short Circuit (contact bypassed) or Open Circuit (wires cut). This supervised circuit gives the most
feedback on the input’s condition, along with Type 4 for Normally Open contacts.
When using a Type 3 or Type 4 EOL Circuit and a Request to Exit button that has a single pole switch, make
sure that the 10K Ohm resistor is on the input leg of the circuit, not the ground side of the circuit, or the Door
Lock and/or Request to Exit status may not work properly, as shown below.
Contact Door Contact Voltage Range
Type 3 - Normally Closed Contact
Switch Closed
Switch Open
Circuit Open
Circuit Short
Door Open
Door Closed
Trouble (open)
Trouble (shorted)
1.17 - 2.89
2.90 - 4.02
4.03 - 5.00
0.00 - 1.16
10
KOhm
21
Input
10
KOhm
N.C.
Request to Exit
Door Close
Request to Exit
Trouble (open)
Trouble (shorted)