INSTRUMENT MANUAL
VACUUM GAUGE MODEL MM200
160Phone:(215) 947-2500 fax:(215) 947-7464 e-mail:sales@televac.com web site:www.televac.com
MM-200_im REV M
Page 32 of 160
TELEVAC
COLD CATHODE MODULE
- The rear panel of the cold cathode module is shown in Fig. 3.8. The gauge tube
cables can be connected by inserting the cable connector into the socket and turning the shell clockwise to engage
the lugs for retention of the connector. An analog output (normally 0 to 10VDC) is available at the connector in the
center of the panel. There are three terminals available. The lower terminal is a common ground and negative
terminal for both the upper two terminals. The upper two terminals are for + 10 volts and + 10 millivolts
respectively. Above the analog “0-10V
" output terminal is a 10
-3
, a 10
-5
or a span adjust potentiometer. These
potentiometers are used, if required, for calibration and to compensate, over a limited range, for effects of
contamination from the process in the vacuum chamber. There is a phone jack labeled “starter” above the
potentiometers for the 7FCS 6200-285 module only. The "ION-ON" potentiometer is not used for the MM200 and its
setting is ignored.
Fig. 3.8 - Rear Panel of the Cold Cathode Gauge Module
3D HOT CATHODE RESIDENT MODULE (I
2
R DEGAS)
- The rear panel of the 3D hot cathode resident module
with resistive (I
2
R) degas is shown in Fig. 3.9. This module occupies 4 module slots. The module must be within
10' (100' with a special cable) of the sensor (gauge tube). No station should be numbered higher than #5.
The sensor power and control cable is connected to the socket in lower right-hand side of the module. Push plug
straight in until the connector "clicks" into a locked position. To remove, press on the sides of the connector, until
the locks are released, and then pull straight out. The sensor ion collector cable is connected to the module via a
BNC connector located in the left-hand middle of the module. Push the mating connector in and twist clockwise to
secure. Above the BNC connector is a case ground connection used to connect the unit independently to a "good
earth ground". Below the BNC connector is a switch marked TUBE TYPE and above the sensor power cable
connector is a sensitivity selector switch. For use see Table 3.4.
ADJUST
ANALOG OUTPUT
COLD CATHODE
CABLE CONNECTION