TDI XBL 400, Инструкция по эксплуатации и программированию

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AC Input Wiring Tips
A standard U.S. three-prong cord is provided with your Dynaload. The voltage selector tab is
mounted to the left of the three-prong AC connector (see figure 6)
WARNING:
The power cord provides a chassis ground through a third conductor. Make
sure that your power outlet is of the 3-conductor type with the correct pin
connected to earth ground. Always Connect the AC cord first to your
Dynaload and THEN to the utility outlet.
Fuse Replacement
The AC input fuse is located inside the voltage selector tab. The fuse replacement part numbers
for the Dynaload are:
US , (3 Amp, 250 Volt, slow
blow)
1.5 inch American
version, or equivalent
MDA-3
UK
,
250V (3.15 Amp, 250
Volt, slow blow)
20 mm European
version) or equivalent.
GDC-3.15A-250V
Table C: Fuse Requirments
Current Interrupt Circuit (Option)
When the Current Interrupt circuit is activated all current flow and the current drive control to
each module is shut down in approximately 5 microseconds.
The loads power section consists of power modules with F.E.T.s (Field Effect Transistors). The
number of FETs and modules vary from model to model depending on the units maximum power
rating. These FETs equally share the loads current.
On the back of each load with the current interrupt option is a BNC connector. The Current
Interrupt is activated by a closed contact shorting the BNC connector. For a smooth transition of
current from Set Point Amps to zero Amps a method of closure with
no contact bounce should be
used. An NPN type transistor (open collector) can be used. The positive (center pin) of the BNC
connector is 15 VDC or less and shorting the BNC connector will draw less than 10 milli amps.
When the Current Interrupt circuit is activated two things happen, all the FET gates are pulled
down to a negative voltage thus shutting down all current flow in approximately 5 micro seconds
and the current drive control to each module is shut down.
Care should be taken with regard to the cable length between the load and the power source.
Since the longer the cables the higher the cable inductance, when current flows an electro-
magnetic field charges about the cables. When the current is abruptly cut off (as in actuation of
the current interrupt) the field collapses and a high voltage spike will occur, depending on the
amount of current and the inductance. For this reason the cable length should be as short as
possible and the positive and negative cables should be twisted around each other. This will
minimize the inductance and voltage spike.
The loads operation manual has two sections, “Effects of Cable Inductance on Pulse Loading”
and “Effects of Cable Length.” This will give additional information.
The Master/Slave Connectors
These two RJ 12 connectors are used for synchronized parallel Dynaload operation. The two
connectors are labeled “Parallel Master Out” and “Parallel Slave In” ).
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