Specifications

molbox™ RFM™ OPERATION AND MAINTENANCE MANUAL

1. High Isolation: Open

2. Low Isolation: Closed

3. Bypass: Open

4. Mirorange Bypass: Open

Figure 6. molbox RFM

Internal Pneumatic Schematic – TARING molbloc-S OPERATION

 OPERATION

To access the TARE function press [TARE], <1tare>. The display is:

1. The current pressure read by the upstream

(left) and downstream (right) RPTs without

taking into account the current tare value.

These are untared readings in the current

pressure units.

2. <T>, to indicate that this is a TARE display

showing the tare between the two absolute

RPTs.

3. The difference between the untared upstream

and downstream absolute pressure readings

(upstream – downstream). This differential

value is always in Pascal [Pa].

4. Tare message

<OK> If tare is less than 300 Pa,

<CHECK> if tare is between 300 and 1250 Pa

<NEED CAL> if tare is greater than 1250 kPa

201.032 kPa ^201.013

T 19.3 Pa OK

The tare screen shows the upstream and downstream RPT readings

WITHOUT the current tare applied. The [P&T] screen shows the RPT readings

WITH the tare applied (see Section

3.4.5).

3.4.4.2 <2Purge>

 PURPOSE

To purge the lines between the molbloc and the molbox RFM and the internal

molbox RFM volumes of one gas with another gas by setting up an internal

valving configuration in which gas flows through the molbox RFM.

 PRINCIPAL

molbox RFM supports the measurement of flow of a variety of gases. To

calculate the flow, the thermodynamic characteristics of the gas must be known.

These are stored in molbox RFM memory. For the flow to be calculated

correctly, the gas flowing through the molbloc must be the gas that is selected on