Metal Samples MS2500L, Руководство оператора

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E. Zeroing Adjustments
Connect shorting plug to J1. Set switch SW1 to the position and SW2 to the Track position.
Using the second DVM, connect the positive lead to pin 6 on AR2 and the negative lead to wire on
shorting plug.
Adjust R12 until a reading of 0.0 mV ± 0.1 mV is shown on second DVM.
Move same two leads to pins 2 and 3 on AR7 and adjust R46 until it reads 0.0 mV ± 0.1 mV.
While looking at other (original) meter, adjust R25 until the current reads 4.00 mA.
F. Current Span Adjustment
Replace shorting plug with the instruments meter cable. Insure that 10 MPY prover is still in place.
Hook the positive lead on second DVM to the (A) red position on J1/J5 and the negative to the (B)
blue position on J1/J5. Set meter to read in the 20 mV range.
Set SW1 to the LPR position, SW2 to the Sample, SW3 to 0, SW4 to 0 and SW5 to 4.
Turn off power supply, wait one second and turn it back on. Let instrument sit for one full minute.
Note: During this time, the second DVM will cycle from 0 mV to ~10 mV every 24 seconds.
During the time that the DVM reads ~10 mV, adjust R3 until the meter reads 10.00 mV ± .01mV
exactly. You have 24 seconds to do this before next cycle.
Once R3 is adjusted, observe meter for two more cycles to insure that 10.00 mV ± .01mV is held.
Remove leads from J1/J5. Adjust R45 until original meter reads 5.60 mA.
G. Disconnection
Remove power from power supply and remove all leads.
Replace connectors and instrument shield. Put instrument back in the condition that it was first received.