3
Electrical Characteristics
(Over the Operating Range)
PARAMETER
CONDITION
MIN TYP MAX UNITS NOTES
Supply Current
24 V DC – TX unit
125
mA
24 V DC – RX unit
75
mA
7
Power Consumption
12 V to 32 V – TX unit
3
W
12 V to 32 V – RX unit
1.8
W
7
Signal input Current
24 V input
1
mA
Signal input resistance
22
k
Ω
HIGH level Trigger Voltage
21
V
1
LOW level Trigger Voltage
3
V
1
Signal input to output delay
12
ms
5
RS-485 input to output delay Optional
40
us
RS-485 baud rate
Optional
0
9600
baud
Audio Input and Output Level 0 dB LED turns ON
-3
dBu
2
Audio Headroom
6
dB
3
Audio sample rate
43
kHz
Audio resolution
20
Bits
Audio Output Resistance
Hot or Cold to Gnd
22
Ω
Frequency Response
16 Hz to 16 kHz
± 1.5
dB
4
Signal-to-Noise Ratio
0 dBFS digital
90
dB
4
Total Harmonic Distortion
0 dBFS digital
0.006
%
4
Signal output Current
Transistor output pull down
500
mA
8,9
Notes
1. The Signal input voltage should never be allowed to be between the maximum LOW-
level, and the minimum HIGH-level input voltage.
2. The input and output level are between the hot and cold terminals. Peak-to-Peak voltage
is 0.775 V, with RMS voltage 0.548 V.
3. Extra output level available before the output clips after the input level has reached the 0
dB level. Thus the output will clip at +3 dBu with Peak-to-Peak voltage of 1.55 V and
RMS voltage of 1.095 V.
4. These parameters are characterized but not tested.
5. Delay from when the TX unit received an input, until the RX unit's output switches ON or
OFF.
6. Power supply and all Signal inputs have reverse voltage protection on TX.
7. The current is the supply current through the +24 V supply line. If all outputs are ON,
the supply current should increase by less than 10 mA. This is because the relay outputs
are pulled down, thus the relay current goes through the GND terminal.
8. The relay outputs are in 3 banks of 8 outputs each. If all 8 outputs per bank are ON
permanently, they are each allowed to draw only 125 mA. Only use 24 V relays, with a
resistance of more than 200 ohm.
9. Each relay output has a 22 k pull-up resistor and a protection diode connected directly to
the 24 V supply.
Caution
The output transistors do all have diode protection, but the outputs can still be damaged if
care is not taken. When a relay is disconnected while an output transistor is on, and the
relay has no diode directly connected to it, the relay will generate a high voltage oscillation,
arcing over the point where contact was broken. This reverse voltage will flow back to the
transistor and damage it.
4
Detailed Pin Descriptions - Transmitter
Pin
Number
Description
C
OMPONENT
S
IDE
Pin
Number
Description
T
OP
C
ONNECTOR
Pin
Number
Description
B
OTTOM
C
ONNECTOR
1
Ground
1
Input 1
1
Input 13
2
+24 V Supply
2
Input 2
2
Input 14
3
RS-485 Ground
3
Input 3
3
Input 15
4
RS-485 IN Hot
4
Input 4
4
Input 16
5
RS-485 IN Cold
5
Input 5
5
Input 17
6
Audio Ground
6
Input 6
6
Input 18
7
Audio IN Hot
7
Input 7
7
Input 19
8
Audio IN Cold
8
Input 8
8
Input 20
9
Input 9
9
Input 21
10
Input 10
10
Input 22
11
Input 11
11
Input 23
12
Input 12
12
Input 24
Detailed Pin Descriptions – Receiver
Pin
Number
Description
C
OMPONENT
S
IDE
Pin
Number
Description
T
OP
C
ONNECTOR
Pin
Number
Description
B
OTTOM
C
ONNECTOR
1
Ground
1
Output 1
1
Output 13
2
+24 V Supply
2
Output 2
2
Output 14
3
RS-485 Ground
3
Output 3
3
Output 15
4
RS-485 OUT Hot
4
Output 4
4
Output 16
5
RS-485 OUT Cold
5
Output 5
5
Output 17
6
Audio Ground
6
Output 6
6
Output 18
7
Audio OUT Hot
7
Output 7
7
Output 19
8
Audio OUT Cold
8
Output 8
8
Output 20
9
Output 9
9
Output 21
10
Output 10
10
Output 22
11
Output 11
11
Output 23
12
Output 12
12
Output 24