HYDRA
Service Manual
4-12
7.
The RTD Temperature Accuracy test is complete. However, if you desire to perform
this test on Input Module channels (2 through 10), repeat steps 1 through 5
substituting in the appropriate channel number.
Note
The only type of temperature measurement that can be made on channel 0
is 2-terminal RTD. Channels 11 through 20 support only 2-terminal RTDs.
Table 4-5. Performance Tests for RTD Temperature Function (Resistance Source)
Decade Reisitance
Simulated
°
C Temperature
Temperature Accuracy Specifications
Source
2620A/2635A*
2635A*
1 Year @ 18-28
°
C
100
Ω
200
Ω
300
Ω
0
266.58
558.00
0
266.34
557.70
±
0.24
°
C
±
0.48
°
C
±
0.75
°
C
*
RTD temperature linearizations changed between the 2620A/2625A and 2635A Hydra instrument
firmware. The 2620A & 2625A Hydra instruments are based on the International Practical Temperature
Scale of 1968 (IPTS-68). The 2635A Hydra Instrument is based on the International Temperature Scale
of 1990 (ITS-90).
These figures assume that RTD R0 is set to 100.00
Ω
for each channel.
Accuracy given is for 4-wire measurements only.
4-12. RTD Temperature Accuracy Test (Using DIN/IEC 751).
1.
Switch OFF power to the instrument and disconnect all other high voltage inputs.
2.
Remove the Input Module from the rear of the instrument. Open the Input Module
and connect a Platinum RTD, conforming to the European Standards IEC 751 (DIN
43760).
2-terminal RTD: Connect the RTD excitation leads to the H (high) and L (low)
terminals of channel 1.
4-terminal RTD: Connect the RTD excitation leads (one red and one black wire) to
the H (high) and L (low) terminals of channel 11. Connect the second pair of RTD
red and black leads to the H and L leads of channel 1. (Refer to Figures 4-1 and 4-2
for proper connection.) Reinstall the Input Module into the instrument.
Note
4-terminal connections are made using pairs of channels. 4-terminal
measurements can only be made on channels 1 through 10. Their
accompanying pairs are channels 11 through 20.
3.
Switch the instrument ON.
4.
Insert the RTD probe and a mercury thermometer in a room temperature bath. Allow
20 minutes for thermal stabilization.
5.
Depending on the type of connection made in step 2, select either the 2-Terminal or
4-Terminal RTD temperature function, RTD type PT (DIN IEC 751), for channel 1
on Hydra. Press MON and ensure the display reads the temperature of the room
temperature bath (within tolerances shown in Table 4-6) as measured by the mercury
thermometer.
Summary of Contents for 2620A
Page 4: ......
Page 18: ...HYDRA Service Manual 1 2...
Page 48: ...HYDRA Service Manual 1 32...
Page 140: ...HYDRA Service Manual 3 16...
Page 234: ...HYDRA Service Manual 5A 34...
Page 236: ...HYDRA Service Manual 6 2...
Page 254: ...HYDRA Service Manual 6 20 2620A 1601 s63f eps Figure 6 3 2620A 2625A A1 Main PCA...
Page 258: ...HYDRA Service Manual 6 24 2635A 1601 s64f eps Figure 6 4 2635A A1 Main PCA...
Page 260: ...HYDRA Service Manual 6 26 2620A 4002 CKT 1 CKT 2 s65f eps Figure 6 5 A2 Display PCA...
Page 272: ...HYDRA Service Manual 6 38...
Page 274: ...HYDRA Service Manual 7 2...
Page 282: ...HYDRA Service Manual 7 10...
Page 284: ...HYDRA Service Manual 8 2...
Page 285: ...Schematic Diagrams 8 8 3 Figure 8 1 A1 Main PCA 2620A 2625A 2620A 1601 s88f eps...
Page 288: ...Schematic Diagrams 8 8 6 Figure 8 1 A1 Main PCA 2620A 2625A cont 2620A 1001 3 of 4 s73f eps...
Page 292: ...Schematic Diagrams 8 8 10 2635A 1001 2 of 5 Figure 8 2 A1 Main PCA 2635A cont s76f eps...
Page 293: ...Schematic Diagrams 8 8 11 2635A 1001 3 of 5 Figure 8 2 A1 Main PCA 2635A cont s77f eps...
Page 296: ...Schematic Diagrams 8 8 14 2620A 4002 CKT 1 CKT 2 Figure 8 3 A2 Display PCA s90f eps...
Page 300: ...Schematic Diagrams 8 8 18 2620A 1003 2 of 3 Figure 8 4 A3 A D Converter PCA cont s82c eps...
Page 301: ...Schematic Diagrams 8 8 19 2620A 1003 3 of 3 Figure 8 4 A3 A D Converter PCA cont s83c eps...
Page 302: ...Schematic Diagrams 8 8 20 2620A 1604 Figure 8 5 A4 Analog Input PCA s92f eps...
Page 304: ...Schematic Diagrams 8 8 22 2620A 1605 Figure 8 6 A5 IEEE 488 Interface PCA 2620A Only s93f eps...
Page 306: ...Schematic Diagrams 8 8 24 2625A 1606 Figure 8 7 A6 Memory PCA 2625A s94f eps...
Page 310: ...Schematic Diagrams 8 8 28...
