T&R PCU2 mk5, Operating And Maintenance Manual

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1.2.3 Output Lead Set Ratings
The optional 3000AL, 4000AL, 5000AL, 6000AL lead sets supplied for use with the PCU2 are
made up from a number of 70mm
2
cores and have different continuous and intermittent
ratings. The rating is also affected by the arrangement of the individual 70mm
2
cables making
up the high current cable. The leads are supplied with the cables strapped together, but to
achieve their maximum rating the straps must be cut and the cores laid out side by side whilst
testing.
Lead set type
Continuous rating
5 minute on/ 15
minute off rating
1 sec on/ 1
minute off
rating
Cores strapped
together
Cores laid out
flat
Cores strapped
together
Cores strapped
together
3000AL 1200A 3000A 1500A 6000A
4000AL 1400A 4000A 2000A 8000A
5000AL 1600A 5000A 2500A 10000A
6000AL 1800A 6000A 3000A 12000A
8000AL 1800A 6000A 3000A 12000A
CAUTION
The cables and terminals will become hot in use. Ensure adequate cooling time is allowed
before touching cables or connectors after tests.
Note: The output leads should not be rested against any sharp edges whilst testing. The insulation
on the cables softens as it heats up, and it is possible for sharp edges to damage the
insulation on the cable under these circumstances. Eddy current heating may occur in ferrous
metals that the pair of cable rests against, and this could heat the cable insulation further.
1.2.4 Metering
The output current is metered by a digital memory ammeter with an LED display. The current
reading is continuously updated when the output is energised, and the value held when the
output is de-energised.
In timing modes where the contact inputs are used to signify the end of a test, the last valid
current measurement before the contacts changed state is held. This also occurs when using
the current operated timer mode.
The ammeter’s minimum response time is 200ms to capture a reading. If the duration of the
cur
rent is less than 200ms the ammeter’s display will display “Err”.