CUB
-
CUB (current unbalance) is factory set to 7%. SymCom recommends the motor
manufacturer be contacted for an exact setting.
The CUB is calculated as follows:
% CUB = [(Maximum deviation from the average)/Average] x 100%
Example:
Measured line currents = 38, 41, and 39, so the average = (38+41+39)/3
= 39.7. The maximum deviation for the average is the biggest difference
between the average current (39.7) and any one current reading, 39.7-38=1.7,
41-39.7=1.3, and 39.7-39=.7, therefore, the maximum deviation from the
average is 1.7. The CUB is then 1.7/39.7 x 100 = 4.3%.
The CUB protection can be disabled by programming 999 in this setting. This will disable
current unbalance protection and current single phasing protection.
PWS
-
PWS (power scale) is the range setting for the LPR and HPR settings.
LPR-
LPR (low power setting) is used to shut down the
motor or pump on an underload condition. Setting
LPR to 0 disables the underload trip feature. LPR is
set in either kilowatts (kW) or horsepower (hp)
depending on the PWS setting.
NOTE: PWS must be set before setting LPR.
HPR-
HPR (high power setting) is used to shut down the
motor or pump on an overpower condition; unit will
display “HPR.” The high power trip uses the motor
cool down timer (RD2) to delay restarts. The Model 777-AccuPower is shipped from the
factory with this feature disabled (“OFF”).
RD1
-
RD1 (restart delay one) is the rapid-cycle timer in seconds. This timer is initiated when
power is first applied to the unit. If no SP or RP conditions exist when power is applied to
the device, the output relay will energize (the NO contact will close and the NC will open)
once the RD1 timer expires. Typically, this is set to 20-30 seconds. This will provide
adequate protection for successive power outages or short cycling caused by other motor
controls. This timer is also initiated when another control shuts the motor off (current goes
to zero). If the user does not want the unit’s relay to de-energize when another control
shuts the motor off, then RD1 should be set to zero. This will also ensure when an alarm
circuit is used, the alarm will sound only when there is a true problem or when power is
lost.
RD2
-
RD2 (restart delay two) is the restart timer used when the unit has shut off due to current
unbalance, current single-phasing, overload, or high power condition. This timer is known
as a motor cool-down timer. RD2 can be set from 2-500 minutes or 0, which will require a
manual reset for these fault conditions. A setting of 5-10 minutes will give most motors
adequate time to cool down after an overload condition. The motor manufacturer should
be contacted for an exact value.
PWS
LPR
& HPR RANGE
1
.01-.99 kW
2
1.00-9.95 kW
3
10.0-99.5 kW
4
100-650 kW
5
.01-1.32 hp
6
1.34-13.3 hp
7
13.4-133 hp
8
134-871 hp
Phone: 800.894.0412 - Fax: 888.723.4773 - Web: www.clrwtr.com - Email: [email protected]
