Amptec Research 620A 4R, Operation And Maintenance Manual

Option "401" is partially a 4-wire lead set (up 
to the probe tip, 2 and 2 style) terminated 
with single handheld probe test points.  The 
“401” also has the standard 620A 4R dual 
banana lead plugs that connect directly to the 
main 620A 4R   measurement panel mount 
banana jacks (red and white).  The 4-wire 
config-uration is maintained up to the point of 
the probe, eliminating most cable resistance 

Option  “300” - Gold Plated 4 Wire Kelvin 
Clip Test Lead Set

 -

shown above 

Option 305:  Banana-to-Banana Cable

Option "305" is a 48" shielded cable termi-
nated in dual banana plugs at both ends.

Option 320:  Kelvin Clips

Option "320" are the gold plated kelvin clips 
used on the Option "300" cable set .  These 
clips may be used when making custom cables 
or when repairing Option "300". 

(see photo on 

previous page)

Option 360:  Heavy-Duty Clips

Option "360" are Gold-plated jumper cable   
(large jaws) type clips used on the Option 
"350" cable.  They are still Kelvin Clips 
because the insulated upper and lower jaw 
integrity is maintained. These may be used 
when making custom cables or when repairing 
Option "350".

Option "403"Kelvin 
    Mini-Probe 
     Test Lead Set

Magnified Tip Close-up

Option "403"

4 Terminal Kelvin Mini-

probes

 -

 (photo shown above)  

Each probe has two

spring loaded, gold 

plated,

steel tips

 with 0.18" separation.

(one 

red and one black handheld probe). Excellent 
general purpose 4 Wire Kelvin Mini-Probe, 
and along with the Option "300" Kelvin Clip 
Leads easily fit inside the AMPTEC 620A4R 
Test Lead Storage Area in the units lid.). 

Option 401: Handheld Single Probe Leads

Option "401" is a 620A handheld probe (one black 
probe & one red probe ) lead set terminated in 

sin-

gle points

.  The OP401 handheld probes allow for 

easy access to connector socket wiring (i.e. drone 
parachute squib sockets), recessed surfaces, and 
parts (i.e. flares) that alligator clip leads simply 
would not work well with.      

Option 620ISO - Isolated Analog Output

for automated resistance measurements

This front panel mounted isolated analog
output provides an Isolated Analog DC 
Voltage output signal that is directly 
proportional to 620A ohm display 
measurement. (i.e. 0.5 VDC for 5.000 ohms, 1 
VDC for 10.000 Ohms). Option 500 is useful 
for tracking 620A Igniter Tester  
measurements for datalogging purposes with 
an external device (i.e. chart recorder, or 

system DMM or DVM with GPIB

). The 

isolation (OP500) provided is rated @2000 
Volts peak, to insure that any datalogging 
instrument connected to OP500 has virtually 
no danger of effecting or impacting the 620A 
Failsafe Ohmmeter’s safety.