iET PRS-300 Series, Руководство по эксплуатации, Страница: 36 / 50

MAINTENANCE
PRS-300 Series
26
The PRS-300 consists 43 internal resistors
which are combined in either series or paral-
lel to achieve the programmed resistance. The
gold shorting links must be removed on the
binding posts of the PRS-300.
These resistors require periodic measure-
ment to keep the PRS-300 within published
speci
fi cations. The resistors are measured
using a DMM. The measured value is then
stored in a table within the memory of the
PRS-300. The measured values of the resistors
are used in an algorithm to determine which
resistors are used to create the programmed
resistance value.
In addition to the 43 resistors the residual
internal lead resistance is also measured at time
of manufacture and entered into memory. The
internal lead resistance does not need to be
measured again unless repair has been per-
formed to the PRS-300.
Below is a list of the 43 resistors and
their nominal resistance value. These resistors
should be within ±1% of the nominal value for
R1 to R5 and ±0.1% of the nominal value for
R6 and higher to ensure proper operation of the
PRS-300. If the measured value of the resis-
tor is outside of these speci
fi cations service is
required.
Resistance
Number
Nominal Resistance
Value
R1 0.17 Ω
R2 0.35 Ω
R3 0.7 Ω
R4 1.37 Ω
R5 2.66 Ω
R6 5.15 Ω
R7 10.2 Ω
R8 20.0 Ω
R9 38.8 Ω
R10 75.6 Ω
R11 148.0 Ω
R12 287.0 Ω
R13 570.0 Ω
R14 1.13 k Ω
R15 2.23 k Ω
R16 4.4 k Ω
R17 8.7 k Ω
R18 17.0 k Ω
R19 33.3 k Ω
R20 66.0 k Ω
R21 130.0 k Ω
R22 258.0 k Ω
R23 506.0 k Ω
R24 1.0 M Ω
R25 2.0 M Ω
R26 3.99 M Ω
R27 7.8 M Ω
R28 15.0 M Ω
R29 30.0 M Ω
R30 60.0 M Ω
R31 120.0 M Ω
R32 3.55 k Ω
R33 7.39 k Ω
R34 16.4 k Ω
R35 33.8 k Ω
R36 72.2 k Ω
R37 147.0 k Ω
R38 300.0 k Ω
R39 600.0 k Ω
R40 1.23 M Ω
R41 2.48 M Ω
R42 5.0 M Ω
R43 10.0 M Ω