Nordson 3100V Series Customer Product Manual

B 2-26 Control
Checking an RTD
or
RTD
Circuit
(contd.)
Table B 2-6 Measuring RTD Resistance
Quick
Methods
ln-Depth Methods
Using
a surface-temperature
sensing device, such
as a
thermocouple,
measure the temperature
of the RTD at
or near the end of the RTD
that is accessible. Then use
an ohmmeter
to measure its resistance
(See
Note A).
See Figure B 2-6
and compare the resistance reading to
the RTD's normal resistance
at the known temperature.
Let
the system
cool
down to room temperature.
When
the RTD has had time to reach room temperature, use
an ohmmeter to
measure its resistance
(See
Note A).
See
Figure B 2-6 and compare the resistance reading
to the
RTD's normal
resistance at room temperature.
Roughly
estimate the temperature
of the RTD to the
nearest
50
'C
(100
'F).
Use
an
ohmmeter to measure
its resistance
(See
Note
A). See Figure B 2-6
and
compare the resistance
reading to the RTD's normal re-
sistance at the estimated
temperature.
Because
RTDs
usually fail open or closed,
any
resistance
reading from
approximately 100-400
ohms strongly indicates'that
the
RTD is
good.
Remove
the
RTD and heat it to
a
known
temperature
by using an oven or by
placing
it
in boiling
water
(pro-
tect the wires and hold them above the water). Then
use an ohmmeter to measure its resistance
(See
Note A).
See
Figure B 2-6 and compare the re-
sistance reading to the RTD's
normal resistance
at the
known temperature.
NOTE A: lf
the
faulted
zone is
a
hose
or
gun,
measure the RTD resistance at the hose or
gun
electrical
plug.
Refer to
your
hose or
gun
manual for a diagram of the electrical
plug
and for
procedures
for checking
RTD resistance.
Because the core
elements of a hose are not accessible,
you
cannot use some of the
methods
described in this table to measure
the temperature of a
hose RTD. lf the
faulted
zone is
a
tank, meadure
the resistance at
pins
33 and 34 of the
harness
attached to
connector XP2
on the control
board.
41
-3000v
lssued 5/00
O
2000 Nordson Corporatlon
All
righls
reserved
82EN-04-[3V-X-4XXVl-5

Nordson 3100V Series Specifications

General

Brand	Nordson
Model	3100V Series
Category	Melting Machines
Language	English