The AMPTEC 620UK Explosive Safety Ohmmeter Front Panel Test Lead Connection uses pin
A
of the
connector is the
Voltage
High
, pin
B
is
I
(current)
High
, pin
C
is
Current Low
and pin D is
Voltage low
.
The last pin (Pin E) is chassis ground and/or can be used as a “shield” around the other lines in your test lead
wiring.
Resistance
under
Test
AMPTEC 620UK
Explosive Safety /
Ohmmeter
Test Lead Length Resistance
Contact Resistance
Pin A- Wiring
Pin B- Wiring
V
HI
I
HI
V
LOW
I
LOW
D-2.6 Zero (Front Panel Knob) ( * * All V4 - Kelvin version users keep the zero knob far clockwise position)
The AMPTEC 620UK Explosive Safety Ohmmeter externally a “2-Wire” type of ohmmeter.
See diagram below .
( Disregard all references to using the "zero Knob" if you have a V4 Kelvin version)
The AMPTEC 620UK Ohmmeter when measuring resistance -
measures the total
of : three “in-series” items
as shown above. The first item is the actual test lead wiring resistance coming from pin A (
Voltage Low
and
Current Low)
and pin B
(Voltage
High
and
Current High).
Test lead resistance depends upon lead length
and gauge of wiring. The second “in-series” item in the resistance measurement loop is the “contact resistance”
of the lead contact when connected to the
“
resistance under test
”
(i.e. squib).
The third item in the resistance
measurement loop is the “resistance under test” which can be virtually any level or magnitude of electrical
resistance as shown in the diagram above. The AMPTEC 620UK Ohmmeter test lead wiring can be a source of
measurement
Pin A=
V
High
AMPTEC 620UK Front Panel Test Connector
( V4 version shown)
Pin B=
I
High
Pin D=
V
Low
Pin E= Chassis Ground (shield)
11
Pin C=
I
Low
