TC8000 4 to 8CH Audio/Intercom
User's Manual
Rev. 7.0
MNL-80000-01-70
- 12 -
TTL Asynchronous
Similar to the RS-232 interface, the TTL interface utilizes pin 5 for the input (TxD) pin while pin 4
is the output (RxD) pin.
Figure 13. RJ-11 TTL Async Pin Assignments & Connection Diagram
Figure 14. Dry Contact Detector and Closure Logic Diagrams
Dry Contact Closure Detector & Relay Switch (Optional)
For dry contact closure applications, the TC8000 can be used as either the Closure or Detector
depending on which pins are used. The transmitter side has a dry-contact closure detector as
shown in the diagram below. The receiver side has a dry-contact closure relay switch. The
"close" and "open" status is controlled by a relay switch inside the TC8000. It reflects the remote
detector's "on" and "off" status.
The diagram below, illustrates the virtual pin connections for using the TC8000 as either a Detec-
tor (Transmitter) or a Dry contact Closure (Receiver). The RJ-11's pins 4 and 5 are closed at the
transmitter side, the status is reflected at the remote receiver's side RJ-11's pins 2 and 3. The
relay switch on the receiver's side is rated 0.4A DC switching current, with a max load rating of
24VA.
As an option, the relay switch on the receiver's side can be rated 1.8A DC switching current, and
a load rating of 108VA.
