Operating instructions

AMC-DTR Sensor Transmitter User Manual
27
There are two Diagnostics menus useful for driving outputs without exposing the sensor to the
target gas. The OUTPUT SIMULATION menu allows setting the 4-20mA output to virtually any
desired value. This is useful for checking responses of devices receiving the AMC-DTR’s 4-
20mA output. The ACTIVATE RELAYS menu allows tripping of alarm relays (if equipped)
without tripping alarm set-points with the target gas. This is useful for testing alarms events
such as lights and audible devices.
* * * WA R N I N G * * *
A l a r m p r o c e s s i n g w i l l
b e h a l t e d d u r i n g
d i a g n o s t i c mo d e !
E D I T t o c o n t i n u e .
A n y o t h e r k e y t o e x i t .
D I A G N OS T I C S
Ou t p u t S t i mu l a t i o n
R e l a y T e s t
OU T P U T S T I MU L A T OR
Ou t p u t 4 . 0 mA
E D I T t o c h a n g e .
N e x t t o e x i t .
EDIT
A C T I V A T E R E L A Y S
R e l a y 1 O F F
R e l a y 2 O F F
R e l a y 3 O F F
Figure 27: Diagnostics Menus
7.10 RS-485 / MODBUS Setup
The RS-485 MODBUS SETUP menu allows setting the RTU address (if RS-485 equipped) for
each AMC-DTR on the RS-485 network. Each AMC-DTR must have a different RTU address
when communicating on the same 2-wire cable. Baud rate, Parity and Stop Bit are fixed at
industry standard values of 9600, none, and 1 respectively.
R S 4 8 5 MOD B U S S E T U P
R T U A d d r e s s 1
B a u d R a t e 9 6 0 0
P a r i t y N o n e
S t o p B i t 1
Figure 28: ModBus RS-485 Setup Menu
7.10.1 MODBUS Register and Function Code Summary
The following table identifies ST-48 Modbus register locations and function codes.
VARIABLE ALIAS READ FUNCTION CODE WRITE FUNCTION CODE
Read Only Discretes:
Chan 1 Alarm 1 2001 2 NA
Chan 1 Alarm 2 2002 2 NA
Chan 1 Fault 2003 2 NA
Chan 2 Alarm 1 2004 2 NA
Chan 2 Alarm 2 2005 2 NA
Chan 2 Fault 2006 2 NA