DayStar DS-100c, User Manual

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DS-100C Operating Manual page C13
Pre-Charge Fuse
Note: New tracer configuration do not use a pre-charge fuse.
The DS-Tracer uses a pre-charge circuit to apply a negative voltage to the DS-
Tracer load capacitors before taking a curve. The pre-charge fuse (if present)
protects the pre-charge circuit if it is inadvertently active while the DS-Tracer load
capacitors are sweeping an I-V curve. Typically this fuse blows if the DS-Tracer
DISCONNECT switch is turned on or off during the pre-charge cycle. Replace
the fuse with only a 1/4 A Fast 3AG fuse. Refer to the section 5.0 Pre-Charge
Precautions for more details and information on the potential damage the pre-
charge can do to thin-film PV modules.
Note: Only replace this or any other fuse with the DS-Tracer completely
disconnected from the PV array.
PV & Voltage Sense Connectors
When an I-V curve is taken, the load current flows through the test lead into the
large red and black PV connectors. The red and black connectors go to PV array
positive and negative terminals respectively. The PV array voltage is measured
separately to avoid measurement errors caused by voltage drops in the test
leads. The test leads incorporate voltage sense wires that run between the
Voltage Sense connector and the ends of the test leads.
DISCONNECT Switch
The DISCONNECT switch is used to isolate the DS-Tracer from the PV array
when connecting or disconnecting the test leads between the tracer and PV
system. Having this switch in the OFF position ensures that no significant current
can flow into the DS-Tracer while making or breaking connections. This feature
prevents the possibility of an electrical arc and protects the user from possible
injury. Although the DISCONNECT switch should always be OFF when
!