R-K Electronics designs and manufactures electrical automation control components. R-K provides a variety of standard products that have many applications as well as custom products. The custom products are typically designed for use in customer's equipment and machinery control systems.
Three-phase voltage relays are used in applications typically involving three-phase motors. The purpose of the three-phase voltage relays is to avoid damage to a motor because of a line voltage problem. The three-phase relays monitor the line voltage for problem conditions which can include: Over voltage, Under voltage, Phase loss (Single Phasing), Phase Rotation, and Phase Imbalance. If any of these conditions occur, the three-phase relays can be wired into the control circuit to disconnect the motor from the line voltage via a starter or contactor or turn on an alarm. Some units are plug-in, some surface mounted and some are din rail mounted.
Figure 1: MVPL-24A-A1C
Figure 2: ATB-115A-1
Figure 3: ISR-24V-10K
Alternating relays change position each time the control circuit is de-energized. In pumping and compressor applications they will:
1. Switch lead and lag after each cycle.
2. Distribute running time between two pump/compressor systems.
3. Will avoid pulse starts at the beginning of a cycle.
In machine sequencing applications they will:
1. One switch to provide alternate operation.
2. Energize on one stroke, but not on the next stroke.
3. Resets to default position on power up.
Products:
CAB - Plug-in, Alternating Relay
Associated products:
ISL - Intrinsically Safe 2 input latch relay
ISR - Intrinsically Safe 2 channel relay
LLA - Liquid level, Alarm logic
LLD - Liquid level, Drain logic
LLF - Liquid level, Fill logic
QPB - 4 pump sequencer
Time delays are used when there has to be some time sequence between the operation of relays or loads.
Products (Plug-In):
CCB - On Delay, 0.05S to 24H
CDB - Interval On, 0.05S to 24H
CFB - Off Delay, 0.05S to 24H
CLRB - Repeat Cycle, 0.05S to 24H
COB - True Off Delay, 0.05S to 1H
CSB - One Shot, 0.05 to 24H
TGM - On Delay, Multi-Range, up to 10H
TUB - Multi-Function & Multi-Range
Solid State:
MCS - On Delay, 0.10S to 5M
MDS - Interval On, 0.10S to 5M
MGS - Off Delay, 0.10S to 5M
MRS - Repeat Cycle, Up to 5M
MSS - One Shot, 0.10S to 5M
Products:
_RCC - 1 to 4 1-phase supressors with common
_RCS - 1 to 4 1-phase individual supressors
RCD - 3-phase suppressor, 480VAC max.
RCM - 1-phase & 3-phase suppressor, 240VAC max.
RCS - 1-phase suppressor, 240VAC max.
RCS5 - 1-phase suppressor, 480VAC max.
RCY - 3-phase suppressor, 600VAC max.
RDS - DC suppressor, 500VDC max.
SP - Varistors, Analog circuit suppression
TFD - 3-phase suppressor, 275VAC max.
TFY - 3-phase suppressor, 600VAC max.
Products:
MRT - Motor rotation tester, 600VAC max.
PLRO - Separate phase loss & phase reversal output
PRR - Surface, loss & phase reversal, 600VAC
PRS - Surface, phase reversal, 600VAC max.
PVC - Surface, 600VAC contacts
PVCO/L - Surface, 3-phase up to 600VAC
PVM - Plug-in, Adj., up to 480VAC
PVR/L - Surface, 3-phase up to 600VAC
PVT - Din mtg., 3-phase up to 600VAC
TVM - Plug-in, 3-phase up to 600VAC
Products:
ATB - Two hand anti-tie down timer
