6
Section 1
Model 289A Differential Pressure Indicating Switch
Switch Contact Rating:
5.0 Amps @ 125 VAC
5.0 Amps @ 250 VAC, 50/60 Hz
1
3.0 Amps @ 30 VDC (resistive)
1,2
1.0 Amp @ 30 VDC (inductive with arc suppression)
1,2,3
0.4 Amp @ 125 VDC (resistive)
0.2 Amp @ 125 VDC (inductive w/arc suppression)
1. CSA Approved
2. CE Approved (Voltage limited to less than 50 VDC or 35 VAC for CE applications)
3. Arc suppression recommended for inductive loadings
Relay Contact Ratings:
10 Amps @ 150/250 VAC
10 Amps @ 14/28 VDC
1.0 HP @ 208/240 VAC
Relay Coil Voltages:
120 VAC @ 5VA Max.
110 VDC @ 2W Max.
Coil Power Requirement:
DC Relay ........................................ 1.5 Watts
AC Relay ........................................ 2.75 Volt Amps
Accuracy of Indications
Standard (1 or 2 SPDT Switches) .....................±1% of factory calibrated span
(10-349
inches
wc)
.....................±1.25% of factory calibrated span
(350 inches wc to 115 psig)
1 or 2 DPDT Switches (S401) .......................... Add ±1/2% to standard accuracy
Near switch setpoint (±10% full scale) ............. Add ±1/2% to standard accuracy
For suppressed ranges .................................... Add ±1/4% to standard accuracy
3 or 4 SPDT Switches ...................................... Add ±3/4% to standard accuracy
Switch Deadband:
SPDT .............................................. ±5% of full scale DP (max)
DPDT .............................................. ±6% of full scale DP (max)
Accuracy of Repeatability ............... ±0.25% of full scale DP
Nuclear Qualifications
The following
nuclear qualification applications are based on Cameron Engineering
Report 9A-CR3-288A-13 with switch chatter sensitivity addressed in Cameron Engineer-
ing Report 9A-CR3-288A-19:
•
One or two SPDT switches: Radiation Augmented (3 MRads), Full Functional, 12G,
Mild Environment Applications
•
One or two DPDT switches: Structural and Pressure Boundary Integrity Applica-
tions
•
One or two relays: Structural and Pressure Boundary Integrity Applications
•
Three or four independently adjustable SPDT switches: Structural and Pressure
Boundary Integrity Applications