Brainboxes es series ethernet to serial adaptors brainboxes es 551 ethernet to serial device with isolated 1 port software selectable as rs232 rs422 485 full duplex or rs422 half duplex the es 551 has removable screw terminals blocks for easy wiring a slim end on case and integral din rail mount the industrial ethernet to serial has an operating temperature range of 40 to 80 degrees celsius and with 5v dc to 30v dc dual input reverse polarity protected power supply making it perfe