Gauge-tube Pinouts, Thermocouple Vacuum Gauges
|2A sensor, brass with 1/8" NPT||2-2100-10|
|2A sensor, s. steel w/ 1/8" NPT||2-2126-001|
|VacuMini 2A miniature sensor||2-2100-102|
|NASA 2A miniature sensor||2-2100-31|
VARIAN DV531, HASTINGS 531, KJL 5311
The sensor is a pair of wires of two differetn materials in "X" shape,
welded in the center, giving
a symmetrical pattern.
Thermocouple voltage is taken between the two wires. Apparently the
heater current can be applied between any two pins, see note.
1 - wire 1 (and TC pos) 1.6ohm to pin5
3 - wire 2 (and TC neg) 1.2ohm to pin7
5 - wire 1 (and TC pos)
7 - wire 2 (And TC neg)
Tube output: 14mV DC full scale (below 1 milliTorr)
Heater drive: 165mA ~0.6VAC
NOTE: Various suppliers use various pins for heater and TC, no two the same!.
For example, old Hastings-type needle-meters (sold by Duniway, type 531) apply AC heater current through wire2 (pin-3 to pin-7) then they short pin-1 to pin-5, take TC+ from pin 1/5 and TC- from the centertap of the transformer heater winding. But Varian instead wants us to take TC signal from between pin-7 and pin-5 while applying AC heater supply between pin-3 and pin-5 (which sends 165mA through the weld between the crossed wires! Did Varian make a mistake, and publish the DV6 pinout for DV0531 tube?) Yet the KJLC531 vacuum gauge meter applies AC heater across pin-1 and pin-7 (through the weld,) then takes +TC from pin-5, and -TC from pin-3.
EDWARDS D35501000 (actually D355-01-000,) METER MODEL 507
WARNING: no longer sold. See 507 Meter mod to use Televac 2A gauge tube
DIN cable pinout: 1 - n.c. 2 - TC+ (sensor rd wire, 10mV out) 3 - heater (sensor bn wire, 10mA) 4 - TC- (sensor bk wire, gnd return) 5 - heater (sensor gn wire, gnd return)Tube output: 10mV DC full scale (below 1 milliTorr)
NOTE: the heater is isolated from TC junction, so any modified version of Model 507 must use a floating panel meter, or a floating heater supply for the NON-isolated 4-wire gauge tubes "2A" or "KJL-1518"
TELEDYNE-HASTINGS TC TUBES DV-6 ETC.