MegaTec Net485-Y Ethernet Device Server

Introduction

Features

Net485 is to convert RS232 signals of [MegaTec] and other protocols to RS422 or RS485 signals.

Features:

1. CPU is ARM 266MHz 32Bit, system clock is 208MHz, flash memory is 4M, SDRAM is 16M, and built-in watchdog.
2. Net485 normal operating temperature and humidity range is 0℃ to 50℃ and 5% to 95%.
3. FCC, Class B, CE, Rosh approved.

Power Specifications

Item	Minimum	Maximum
DC Input Voltage	+5.3V	+40V
DC Input Current		3W Maximum

Pin Assignment

Pin	Input / Output	Description
P1 GND	GND	Ground PIN
P2 Power In	Input	DC power input
P3 RS232_TXD	Output	+5.5V and -5.5V Voltage level for RS232
P4 RS232_RXD	Input	-3V to -15V for logic ‘1’, +3V to +15V for logic ‘0’
P5-P7 No USE
P8 SNMPSIG		NET485 card plug in detect, connect to PIN 10
P9 GND	GND	Ground PIN
P10 SNMPSIG		NET485 card plug in detect, connect to PIN 8
P11 RS232_DCD	Input	+/-3V to +/-15V for RS232
P12 RS232_DTR	Output	+5.5V and -5.5V for RS232
P13 RS232_DSR	Input	+/-3V to +/-15V for RS232
P14 RS232_RTS	Output	+5.5V and -5.5V for RS232
P15 RS232_CTS	Input	+/-3V to +/-15V for RS232
P16 RS232_RI	Input	+/-3V to +/-15V for RS232
P17-P26 No Use

Signal Specification

Receiver Inputs 

PARAMETER	CONDITIONS	MIN	TYP	MAX
Input Voltage Range		-25V		+25V
Input Threshold Low	TA=±25℃	+0.6V	+1.2V
Input Threshold High	TA=±25℃		+1.5V	+2.4V
Input Hysteresis			0.3V
Input Resistance	TA=±25℃	3 k ohm	5 k ohm	7 k ohm

Transmitter Outputs

PARAMETER	CONDITIONS	MIN	TYP	MAX
Output Voltage Swing	All transmitter outputs loaded with 3k ohm to ground	±5.0V	±5.4V
Output Resistance	TA=±25℃	300	10M
Output Short-Circuit			±35mA	±60mA
Current

Size Specification

Net485-Y Internal Card 

Dimension	137.7mm(L) × 60mm(W) × 43.0mm(H)
Weight	53g±2g
Connector	26pin gold finger

Net485-Y External Card 

Dimension	156mm(L) × 82mm(W) × 32mm(H)
Weight	195g±2g

Net485-Y Adapter

Dimension	42.15mm(L) × 31.08mm(W) × 17.38mm(H)
Weight	12.8g±2g

Usage

Factory Settings

Net485 will be set according to the parameters related to the receiving data side provided by the user before shipping. Because the Net485 parameter setting requires the user to use a direct serial cable (1 to 1, 2 to 2… 9 to 9) connected to the computer side and set up using HyperTerminal. The external card requires the user to remove the case. To see the advanced user settings,
Please contact our technical support.

Ordinary users need to provide the following parameters at the receiving end to our company to make factory settings;

	RS232	RS422	RS485
Device Address	01(Default Value)	01	01
MODBUS Connection Mode	RTU (Default Value)	RTU	RTU
RS Baud Rate	9600(Default Value)	9600	9600
RS Connection Type	RS232 (Default Value)	RS485	RS485
Half Duplex / Full Duplex	Full Duplex (Default Value)	Full Duplex	Half Duplex
Serial Communication Electrical Level	Normal Mode (Default Value)	Normal Mode	Normal Mode

Applications

Users can connect Net485 to UPS and MODBUS receiver or PC for testing.
The following content is an example of [Modscan] software testing.

If you connect Net485 to PC side for testing, you need to prepare your own RS485 to RS232 cable. You can refer to the following diagram for the connection method.

1. Run [Modscan], click Connection, select the PC serial port connected to the Net485 output, and Modbus related settings. As shown in the figure.
   
   
2. Select the holding register and start address to view the received data.
   
3. Look up the UPS data represented by the corresponding address bit in the provided register address file.

Documents / Resources

MegaTec Net485-Y Ethernet Device Server [pdf] Instruction Manual Net485, Net485-Y, MegaTec 2023-7-6, Net485-Y Ethernet Device Server, Net485-Y, Ethernet Device Server, Device Server

References

• User Manual