BECKWITH ELECTRIC M-3425A, Instruction Book

Page: 296 / 482

6–9
Testing – 6
24 Volts/Hz Definite Time (#1 or #2)
VOLTAGE INPUTS:
Configuration V1
CURRENT INPUTS:
None
TEST SETTINGS:
Definite Time Pickup P % (100 to 200)
Time Delay D Cycles (30 to 8160)
Programmed Outputs Z Output (1 to 8)
Expanded I/O (9 to 23)
■ NOTE
: It would be efficient to disable the 24 Definite Time element with the lower pickup setting first and
test the higher setting operation, since the lower setting operation can be tested without disabling
the higher setting.
Test Setup:
1. Determine the Function 24 Volts/Hz Definite Time settings to be tested.
2. Enter the Function 24 Volts/Hz Definite Time settings to be tested utilizing either the HMI or IPScom ®
Communications Software.
3. Disable all other functions prior to testing. Refer to Section 4.4 System Setpoints, for details that
describe disabling/enabling functions.
4. Connect test voltage inputs as shown in Figure 6-1, Voltage Inputs: Configuration V1.
5. The Volts per Hertz pickup level at a percentage setting at Nominal Frequency (50 or 60 Hz) is:
Pickup voltage = (
P
% ÷ 100) x (
Nominal Voltage
) where the Nominal Values have been programmed
in the system setup data described in Section 4.2, System Setup and are recorded on Figure A-2,
System Setup Record Form.
Pickup Test:
1. Press and hold the
TARGET RESET
pushbutton, then slowly increase the voltage on Phase A until
the
24 VOLTS/Hz
LED illuminates, or the pickup indicator illuminates on the IPScom Function Status
screen. The voltage level of operation will equal to
P
volts ±1%.
2. Release the
TARGET RESET
pushbutton, then decrease the Phase A voltage. The assigned
OUTPUT
LED(s) will extinguish.
3. Press the
TARGET RESET
pushbutton to reset targets.
Time Test :
1. Connect a timer to output contacts
(Z)
so that the timer stops timing when the contacts
(Z)
close.
2. Apply approximately (
P
+ 10 volts) volts, and start timing. The contacts will close after
D
cycles ±
25 cycles.
3. Repeat Pickup Test and Time Test for Phase B and C.