Humboldt H-3185B CONTROLLER - Manual (Page 14)

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© 2008 Humboldt Manufacturing
5.2 Setting Holdback Band
1. Continuing from section 5.1, while the green display is alternating between
“rOPt” and “8.r.S” as in step 3 of the previous section, push the Mode button
again until the green display reads “HLd.b” (Figure 11). This is the
Holdback Band function. The green display will alternate between “HLd.b”
and the holdback set temperature variance.
Figure 11
Note: The Holdback Band changes the allowed temperature variance from the set
value. If the actual temperature goes beyond this variance during the cycle, the
ramp timer will stop and the controller will attempt to reach the set value
temperature by switching back and forth between heating and cooling until the set
value is reached before continuing. This setting is preset to 2° which is slightly
less than the 3° variance specified by the ASTM standard at the cycle extremes.
Increasing this setting could allow the test sample to exceed the allowed variance
at the cycle temperature extremes. Decreasing this setting could cause non-
uniform cycling