Keithley 7015-S Instruction Manual

Contents

Keithley 7015-S Instruction Manual Manual pdf 73 page image

Service Information5-11WARNINGThe following steps use high voltage(100V). Be sure to remove power fromthe circuit before making connectionchanges.4. On the Model 617, set the voltage source for +100V, andselect the 200nA current range. Make sure the voltagesource is still in standby.5. Place the Model 617 in the V/I measurement function bypressing SHIFT OHMS.6. With the Model 617 in standby, connect the electrometerto Bank A of the multiplexer card, as shown in Figure 5-6.7. Install the Model 7015 in slot 1 (CARD 1) of the main-frame, and turn on the Model 7001/7002.8. Make sure all the relays are open. (Press OPEN ALL onthe Model 7001/7002.)9. On the Model 617, disable zero check, and press OPER-ATE to source 100V.10. After allowing the reading on the Model 617 to settle,verify that it is >1GΩ (109Ω). This measurement is thedifferential leakage resistance (isolation) of Bank A.11. Place the Model 617 in standby, and enable zero check.Figure 5-6Differential isolation test connectionsABCD1 3 4 5 6 7 8 9 102HLHLHLHLH L H L H L H L H L H L H L H L H L H LBankOutputsBank InputsModel 7015HIModel 617INPUTModel 7025UnterminatedTriax Cable(Red)Banana to Banana CableGround LinkRemovedUnterminatedBanana CableNote : Setup shown is configured totest isolation between HI andLO of Bank A.5.3.8 Differential and common-mode isolationtestsThese tests check the leakage resistance (isolation) betweenHI (H) and LO (L) (differential), and from HI (H) and LO (L)to chassis (common-mode) of every bank and channel. Ingeneral, the test is performed by applying a voltage (100V)across the terminals and then measuring the leakage current.The isolation resistance is then calculated as R = V/I. In thefollowing procedure, the Model 617 functions as a voltagesource and an ammeter. In the V/I function, the Model 617internally calculates the resistance from the known voltageand current levels, and displays the resistance value.Perform the following steps to check differential and com-mon mode isolation:1. Turn off the Model 7001/7002 if it is on, and remove anyjumpers and test leads connected to the multiplexercard.2. Turn on the Model 617, and allow the unit to warm upfor two hours for rated accuracy.3. On the Model 617, select the 2pA range, and enable zerocheck and zero correct in that order. Leave zero correctenabled for the entire procedure.Artisan Technology Group - Quality Instrumentation ... Guaranteed | (888) 88-SOURCE | www.artisantg.com