Alpha Technologies XM2-300CE-HP - Manual (Page 26)

2.0 Installation, continued
2.4 Protective Interface Module Installation (factory installed option)
The optional Protective Interface Module (PIM) adds a second independent output. It
provides programmable current limits for two output channels.
The PIM option protects system components by shutting down the load during overcurrent
and short circuit conditions. The PIM has a programmable overcurrent threshold (3-6A) and
overcurrent tolerance period that specifies the time (1-10 secs) an overcurrent condition is
permitted before shutting down.
You can use the programmable retry limit to select how many times (0-10) after a
programmable delay (60-600 seconds) the PIM will attempt to reconnect an output once it
has been shut down. When the limit is reached, the XM2-300HP power supply automatically
retries once every 30 minutes until the fault clears.
Adding the PIM to the XM2-300HP provides these advantages:
A second protected output: • The main purpose of the PIM is to limit the impact of a fault
condition in one output channel. If a fault condition occurs in an XM2-300HP (without
the optional PIM installed) the entire customer network can be affected. The PIM option
affords protection to one output should a fault condition exist on the other. This gives you
flexibility to isolate Output 1 from Output 2.
A current for critical loads: • With the PIM option, you can designate one output as
the primary connection, and the other output as the secondary connection. Commonly,
critical loads are connected to Output 1 as the primary feeder. Using the overcurrent limit
settings, you can ensure that the primary output always provides the necessary power.
For example, on a 60 volt unit, if a customer needs 3 Amps available on Output 1, the
overcurrent limit for Output 2 is set at 2 Amps, so regardless of Output 2, 3 Amps will
remain available for the primary Output 1.
Additional current protection: • The standard XM2-300HP current limit protection is
provided by the output circuit breaker. The 160% current limit may exceed the ratings
of active devices in the cable network and cause failures. You can lower the maximum
current provided at each output by lowering the overcurrent limit of each respective
output. Therefore, to minimize failures due to excess current supply, set the overcurrent
limit to a value below the maximum current the active components can tolerate.
For example, on a 5A power supply, where both outputs are programmed to 4A maximum,
and both outputs are supplying 3A, neither output is “in violation” but the total system at 6A is
operating at 120% of its rated output. In this example, after 30 minutes, the power supply will
begin a “load shedding” algorithm. The first action is to disconnect Output 2. If this does not
correct the system overload, the next action is to disconnect Output 1.
XM2-300HP Load Permitted Duration of Load
>150% 10 seconds
125% to 150% 10 minutes
115% to 125% 30 minutes
<115% Many months
26 017-877-B1-001 Rev. A