Lake Shore Model 231 User’s Manual
Service
4-1
CHAPTER 4
SERVICE
4.0
GENERAL
This chapter cover general troubleshooting in Paragraph 4.1, Model 231
connectors in Paragraph 4.2, and calibration in Paragraph 4.3.
4.1
GENERAL TROUBLESHOOTING
4.1.1
No Output (On-Board LED Off)
Check that external power supply output is +5 VDC. If not, replace supply.
If using the front panel input jack (J2), make certain center post of connector
coming from power supply is NEGATIVE. If not, correct wiring. If using front
panel input jack (J2), verify external power supply is regulated at +5 VDC
and can supply a minimum of 500 mA. Also verify that OUT+ and SHIELD
are
not
connected to each other.
Due to extensive protection circuitry installed in Model 231, all the above
problems eventually cause the 0.5 A slow blow fuse to burn out. After
correction, replace the blown fuse with identical size and type.
4.1.2
Output Stops Before Reaching Upper Limit
Normally caused by too high resistance of output monitoring device.
Absolute maximum acceptable resistance is 500
. Also verify that proper
range DIP switch is selected.
4.1.3
Output Is Incorrect Value (Small Error)
Can be caused by incorrect curve selection for the sensor type. See
Figure 3-1. Another cause for a small error is the output resistor for output
current to voltage conversion is not high precision. When using voltage out,
the output resistor must be ±0.02% accurate (or better) and have low drift.
Summary of Contents for 231
Page 4: ......
Page 5: ...Lake Shore Model 231 User s Manual ...
Page 6: ......
Page 24: ...Lake Shore Model 231 User s Manual 2 8 Installation This Page Intentionally Left Blank ...
Page 32: ...Lake Shore Model 231 User s Manual 4 6 Service This Page Intentionally Left Blank ...
Page 36: ...Lake Shore Model 231 User s Manual 5 4 Options Accessories This Page Intentionally Left Blank ...
Page 43: ......