Super Systems Gold Probe - Manual (Page 10)

9
SSi Gold Probe Manual Rev C
TROUBLESHOOTING (cont’d)
5. Is the probe impedance less than 50 kilohms
at temperatures above 1550ºF (843  C)?
Conduct the test shown in Fig. 3 using a shunt
resistor greater than 50 kilohms. Measure the
voltage E
C
before shunting, then E
M
with the
shunt in place. Calculate R
P
. If it exceeds 50
kilohms, proceed to step 8, below.
6. How quickly does the probe react to a change
in O
2
concentration? Read the probe millivolts
with the controller or the digital meter. Short
the probe for 5 seconds, remove the short and
measure the time required to return to within
1% of the original reading. If it exceeds 30
seconds, proceed to step 8, below.
7. Is there a leak in the zirconia substrate? To
test this property, turn off the reference air for
one minute. Measure the probe mV as
indicated by the controller or a digital
voltmeter. Turn the air back on and measure
the mV again. If there is a difference greater
than 25 mV, replace the probe.
CONTROL SYSTEMS
If you are using the Gold Probe as a replacement
in an existing system, you will find that
performance is as good as or better than you are
accustomed to. If you plan on a new system to
upgrade your controls, you can rely on Super
Systems to provide you with exactly what you
need. From the simplest on/off controls to the
most sophisticated programmable PID controls
with computer interface, data logging, production
tracking, recipe design, scheduling, reports,
integrated
8. If probe resistance or response times are
questionable as indicated in steps 5 and 6, we
recommend that the probe be burned off.
Introduce 10 to 15 CFH of air to the burnoff
fitting for about 90 to 120 seconds, and then
repeat the tests. Should problems persist, it may
be necessary to conduct a thorough furnace
burnout so that all potentially contributing
contamination is removed from all parts of the
furnace, including the Gold Probe. Burning off
the probe will not harm this product provided
the probe temperature does not exceed 2000ºF
(1093
 C) during the burnoff procedure.
9. Should it be necessary to remove your Gold
Probe from a hot furnace, do so carefully.
UNDER NO CIRCUMSTANCES should
it be removed faster than 2" (51mm) per
minute.
10. Failing resolution of your atmosphere control
problems our technical support staff is available
Mon. - Fri. 7:00 a.m. to 7:00
p.m. to assist and serve our heat treating
customers. Call us at (800) 666-4330.
order entry and invoicing. Fig. 7 and Fig. 8
illustrate simple control and probe conditioning
systems as supplied by Super Systems. SSi is
positioned to provide a “plug and play” system
that is operator friendly. Components such as
valves, flow meters, cable and tubing are
supplied with each SSi system so that no search
and purchase effort is involved in installation.