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> Basler var/power factor controller 99110000209 scp 250
Basler var/power factor controller 99110000209 scp 250
The SCP 250 controls generator (SCP 250-G) or motor (SCP 250-M) power factor or vars by monitoring
the voltage and current and supplying a control input to a voltage regulator.
When the SCP 250 is controlling vars, the voltage regulator (or static exciter) output changes to attain the
selected reactive load current.
When the SCP 250 is controlling power factor, the voltage regulator adjusts the excitation until the
selected power factor is obtained.
The SCP 250 monitors the open/closed state of the circuit breaker so that the voltage regulator controls
excitation when the breaker is open and the SCP 250 controls excitation when the breaker is closed.
A voltage limiting feature in the SCP 250 prevents the voltage regulator from supplying full or no
excitation if utility power is lost and the peaking generator main breaker remains closed. Voltage limiting is
Because the SCP 250 is designed for behind-the-panel mounting, provisions are included for locating the
Var/PF switch and potentiometer remotely.
SCP 250 Var/Power Factor Controllers have the following features.
Suitable for use in generator or synchronous motor applications
Provide system control over a wide range of loading conditions
Accommodate standard voltage sensing inputs
Front panel selection of either var or power factor control
Do not require use of motor operated control
Specifically designed to operate with the standard Basler SR , KR, selected AVCs, SSR regulator
series, and SSE static exciter-regulators
During power factor control, reactive load changes automatically when kW load is changed
UL recognized and CSA certified
The SCP 250 is suitable for use in generator peaking and synchronous motor applications.
Generator Peaking Application (SCP 250-G)
In peaking generator applications, the paralleling circuit of a voltage regulator presents large changes in
reactive current when the bus voltage changes by a relatively small amount. However, the regulator s
ability to compensate for large changes in bus voltage can be exceeded. Two examples illustrate typical
Example 1. A generator equipped with a voltage regulator adjusted for 4% droop can
have a variation in var load from zero to 100% with a 4% decrease in bus voltage.
Further decreases in bus voltage would overload the generator.
Example 2. An increase in bus voltage can cause leading power factor conditions with
the associated danger of the machine pulling out of synchronization.
To minimize the possibility of either example occurring, the SCP 250 is used and adjusted for operation in
a safe region with either a regulated fixed var level or a fixed power factor. Thus, for a large change
in reactive current due to bus voltage changes, the operating generator is unaffected.
