Electron MODBUS works sometime

Hello Everyone,
This is my first post here. Looking for some help.

I have a power meter and it uses MODBUS RTU for communication. I am trying to read data from it using sn65hvd75dr (RS485 transreceiver) breakout board and my Electron. Below is the code.
Problem is: I am able to read data from the power meter to Electron sometimes else it fails and gives error E0,E1,E3 and then all of a sudden it receives correct data and then fails again.
How should I make this reliable?

I tried the RS485 breakout board with arduino and it works fine all the time.
Thank you for the help

// This #include statement was automatically added by the Particle IDE.
#include <ModbusMaster.h>
#include <application.h>

ModbusMaster node(1);
char power_meter[]="";

void setup() {
	// initialize Modbus communication baud rate
	pinMode(D7, OUTPUT);
	node.enableTXpin(D7); //D7 is the pin used to control the TX enable pin of RS485 driver
	while(!Serial.available()) Particle.process();
	Serial.println("Starting Modbus Transaction:");

void loop() {
	static uint32_t i;
	uint8_t j, result, cnt;
	uint16_t data[50];
	uint16_t datahex[50];
	uint32_t out[25];

    digitalWrite(D7, 0);
	result = node.readHoldingRegisters(0x4000,50);

	// do something with data if read is successful
	if (result == node.ku8MBSuccess) {
		Serial.print("Success, Received data: ");
		for (j = 0; j <50; j++) {
			data[j] = node.getResponseBuffer(j);
        out[cnt]= (data[j]<<16) | (data[j+1]);
		float y = *(float*)&out[cnt];
	} else {
		Serial.print("Failed, Response Code: ");
		Serial.print(result, HEX); 
		delay(5000); //if failed, wait for bit longer, before retrying!