envea STACK 710, User Manual

Page: 36 / 68

4 Getting Started STACK 710
36
(PC-000878-MA Issue 7, December 2021)
ENVEA UK Ltd
4.10 Setup Alarm
Note that the Alarm value is expressed in terms of the Output Type (Opacity
, Optical Density or Dust Density ) selected as described in section
.9
.
From Settings , press .
Use the and arrows to select Alarm and press .
Use the and arrows to change the Alarm Level and press Press
to return to Settings .
4.11 Calibration Check
From Settings use the and arrows to select Calibration .
Use the and arrows to select Calibration Check and press
Start is displayed, press to Start the Calibration Check.
The hourglass is displayed while the Calibration Check is in progress.
It disappears when the Calibration Check is finished.
Press twice to return to the main display.
The STACK 710 is now ready for use.
4.12 Modbus Interface
Modbus communications, based on the RS485 duplex hardware standard, provide
direct access to the STACK 710 system data. Details of the Modbus protocol are
available from the Modbus website
www.modbus.org
. The STACK 710 implements
Functions: (Read Holding Register), (Pre-set Single Register) and 10 (Pre-set
Multiple Registers)
Each Modbus must have one termination resistor at each end and one bias
network somewhere on the bus. The STACK 710 can provide a termination resistor
and a bias network. As supplied, the termination resistor is switched on, and the
bias network is switched off. To change these, switch off the power, remove the
rear cover from the Transceiver (see section C -4), and locate switch S1 on the
Main printed circuit board. The four sections of S1 have the following functions:
1 and 2 - Bias network Supplied OFF
- Not used