EM3028B / EM3028B-R / EM3028B-X User’s Manual - Page 1 of 8
Models
EM3028B (version 2.1)
Audio only, no relays.
EM3028B-R (version 2.1)
Audio + relays for simple control.
EM3028B-X (version 1.1)
Audio + relays for complex animation.
Technical Specifications
Operation Mode
playback only
Sound File Format
Windows WAV (uncompressed PCM)
- 22.05 or 44.1 KHz sampling rate
- 16 bit depth
- monaural
Max. Number of Sound Files
Parallel / Direct Mode: 8
Parallel / Binary Mode: 128
Parallel / Sequential Mode: 512
Parallel / Round-Robin Mode: 8
Parallel / Script Mode: 512
Serial Control: 512
Memory Type
CompactFlash card, type I
Max. Memory Capacity
> 1 GB
Max. Recording Time
> 1 hour
Supply Voltage
10 ~ 32 VDC
Typical Standby Current
150 mA
Max. Audio Output
40W (8 Ohm load)
Serial Interface
RS-232 / RS-485
Parallel Interface
8 inputs, CMOS level
Physical Dimensions
EM3028B
6.0’’ x 4.8’’ x 1.7”
EM3028B-R & EM3028B-X
6.0’’ x 7.5’’ x 1.7”
Interface Descriptions
Power Input Terminals: VD & GD
Use a well regulated DC power supply to obtain the best sound quality. Connect the power
supply’s positive output to terminal VD, and the negative output to terminal GD.
Speaker Output Terminals: S1 & S2
The speaker output is bridged (balanced). Depending on the ambient temperature, addi-
tional heat ventilation may be required to obtain maximum output. If not used, the built-in
power amplifier can be disabled by moving the on-board jumper J3 to the OFF position.
Busy Output Terminal: BY
This output is manually controlled when the system runs in the Script mode. In all other
modes this signal is automatically turned on during the playback of any file. The output is
open collector and internally pulled up to +5V through a 10K resistor (R13). It drops to about
0.2V when activated, sinking current up to 100 mA. When controlling an external relay with
this signal, be sure to remove resistor R13, and add a protection diode as shown in the
diagram below.
System Reset Terminal: RS
Short terminal RS to the ground to reset the board. Minimum reset duration is 100 ms.
Parallel Input Terminals: T1 - T8
These inputs are internally pulled up to +5V through 10K resistors, and protected with 1K in-
line resistors. The Parallel Input is enabled by default.
Power Light (PWR)
The power light is turned on when power is applied.
Volume Pot (VOL)
Turn the knob clockwise to increase the output volume. It affects only the speaker output,
not the line output.
Line Output (LINE): 1/8” Mono Phone Jack
This jack provides single ended line output for external amplification.
Serial Port: DB9 Female
The default serial mode is RS-232. To select RS-485, move the internal jumper J2 to the
“485” setting. Note that the Serial Port is disabled by default.
Relay Output Terminals (EM3028B-R & EM3028B-X only)
Three terminals are provided for each relay: NC (Normally Closed), NO (Normally Open)
and Common (the center terminal). The contact is rated at 12A/120VAC or 10A/24VDC.
Typical wiring diagram for push button activation.
