AMPTEC 620ES Rear Panel with RS232C I/O
The AMPTEC 620ES rear panel (shown above) contains
many jacks, terminals, labels, and stickers.
The AC to DC Adapter (item #1) must be left in the
rear panel jack in order to continuously operate the unit,
if fitted with option "247". If configured with NICAD
batteries then this is the battery charger jack and the
620ES will only charge when the power switch is in the
"OFF" position. ( battery powered units only).
Item 2
is the fuse holder - replace with a 2 ampere 3 AG
type fast blow fuse (rarely needs replacing).
RS232C Serial Interface - Item # 3 is the safety isolated
RS232C serial I/O (9 pin D type Sub-min connector ).
This RS232C Interface provides the meter’s resistance
measurements to a PLC fitted with a serial port. The
RS232C protocal settings should be 9600 Baud, 8 Bits
, No parity , 1 Stop Bit ,
9 pin D Sub-min connection
.
RS232C Command Set
(NOTE: All front panel range buttons must be de-
selected (press in half way)
with all range pushbuttons
out
in order to disable with local lockout and enable
RS232C control.
Note commands are case sensitive
.
C
Continuous Read Mode -
RS232C I/O
outputs
a data string every A to D conversion cycle, approx
.
2.5
times per second.
S
Single Read Mode -
RS232C I/O
outputs a
single data string upon reception of a “R” command.
R
Read -
Commands
RS232C I/O
to output a
single data string
( 1 resistance reading).
r
0
De-Selects all Ranges
r1
Selects the 2.0 Ohm Range
r2
Selects the 20 Ohm Range
r3
Selects the 200 Ohm Range
r4
Selects the 200K Ohm Range
V
Version
c
ommands board to output the firmware
version string.
*
Data Format -
The
RS232C I/O
outputs a data
string with the following format:
1.2345E+3
The measurement is always in Ohms
+3
(where E+3 = 10 scientific notation style)
. The
Exponent is defined below.
1.2345E+3 = 1.2345
+3
+3
KOhms
(where E =10 ).
1.3700E+1
=
13.700
+1
+1
Ohms
(where E =10 )
Range
Exponent
2.0
Ohm
E+0
20.0
Ohm
E+1
200.0 Ohm
E+2
2.0 K Ohm
E+3
20 K Ohm
E+4
200 K Ohm
E+5
An overrange condition is indicated by
9.9999E
nn..
Where nn is the
selected resistance
range
exponent. A Range Error is indicated by
x.xxxxERR.
Item # 4
is the unit’s serial number sticker.
Item # 5
is the gold plated 4 terminal rear terminal
strip (they are wired in parallel with the front termi-
nals). If a “2 wire ohms” connection is made then
the
V
high and
I
high terminals should be shorted
together, and the
V
low and
I
low terminals should
be shorted. The 620ES Voltage High, Voltage low,
Current high and Current low wires are perma-
nently connected to the gold plated rear terminal
strip ( seel labeled gold plated terminal strip on rear
panel).
Item #6 Calibration Sticker -
If the calibration
due date has expired ( 1 year) AMPTEC or a Cal.
Lab can contacted to re-certify the AMPTEC
620ES Explosive Safety Ohmmeter/Igniter Tester.
contact AMPTEC customer service see website
