OPERATION -

 

The OPERATION section of the manual assumes that the user has wired the DPC2530 for power and communications according to the TERMINAL BLOCK WIRING and has verified the parameters in the Series 8 controller according to the INSTRUMENT SETUP section.

Flip the ENCLOSURE POWER switch to the on position.  Depending on the noise level, you should hear the sound of a cooling fan and the LED display should also illuminate on the Series 8 controller (Figure 2).  The actual dew point should be displayed in green at the top with the set point and percent output displayed below it in orange. 

Figure 2

 

 

Connect a sampling line to the sampling line inlet on the side of the DP22530 (Figure 3). A brass compression fitting is provided to which a sampling line can be connected.

     

Figure 3

 

 

If the system from which gas is being sampled is under pressure, there should be visible flow in the flow meter.  Adjust the flow through the meter using the adjusting knob on the meter (Figure 4).

 

Figure 4

 

 

If there is no visible flow after the sampling line is connected, the pump will need to be turned on to “pull” a sample through the DP2530.  Flip the PUMP POWER switch to turn on the sampling pump (Figure 5).  You should hear the pump running (depending on the noise level at your location) and the flow through the meter should increase significantly.

 

Figure 5

 

 

To obtain consistent accurate readings from the DPC2530, be sure that the element in the bowl filter on the side of the instrument is clean and functional.  Not only will this ensure that the sample reading is not abnormally high (since soot tends to trap moisture), but it will also prevent soot and other contaminants from entering the unit and damaging the sensor.  The optimum flow rate of the sample gas should be between 1.5 and 2.0 cubic feet per hour (CFH), although a flow rate as low as 1.0 CFH is acceptable (Figure 6).  If the unit is reading less than 1.0 CFH, verify that there are no obstructions to the flow such as a clogged sample line or a poorly adjusted knob on the DPC2530’s flow meter.

 

Figure 6

 

Heat Treat Furnace Sampling: A gas sample may be extracted from a process using the built-in pump.  The sample tube from which the sample is taken out of the furnace should extend into the furnace past the HOT face of the refractory.  For accurate results, a designated sample port should be used to extract the sample.  SSi offers a sample port assembly (part number 20263) which is ideal for this purpose.  If a designated sample port is not available, then a clean “burn-off” port on a Gold ProbeÔ, an industry leading oxygen sensor for atmosphere control, can be used.

 

Endothermic Generator Sampling: For applications under pressure, the pump should be switched off and the flow controlled by the small restriction valve on the flow meter.  A flow rate between 1.5 and 2.0 CFH is ideal.  The sample should be taken from the endothermic gas manifold after the gas has been cooled. NOTE: Allow the sample port “to blow out any soot” before connecting the sample tube.  Failure to do so will unnecessarily coat the sample tubing assembly and possibly some internal components with soot, resulting in inaccurate readings and exposing the sensor to potential damage.