The 3300 Series meter relays offer a wide variety of applications in control, alarm, and limit use. Photo conductor sensing eliminates all interference with the indicating meter. These relays incorporate an amplifier input which drives a rugged high-torque pivot and jewel meter. Metal-cased “Rugged Seal” construction withstands rigorous environmental conditions. The die cast metal case with a drawn steel plated rear case gives complete magnetic isolation for steel panel mounting. In addition, each controller is moisture, dust, and dirt proof for use in wash-down areas. Failsafe circuitry opens output relays in the event of power failure. Two different sizes, 3-1/2" and 4-1/2", are available in both single and dual set point models. High-gain transistor switch circuitry provides accurate switching with a “dead band” of no more than 0.5% of full scale (F.S.). All DC current meters offer ±2% of full scale accuracy. This style meter is ideal for many other electrical functions.
Auto/Manual Reset
There are two modes of relay logic available in the 33 Series: Auto Reset and Manual Reset. Auto Reset is a simple on-off action in which the high set point relay is de-energized when the pointer exceeds the high set point, and is automatically energized when the pointer again drops below the set point. The low set point relay is de-energized when the pointer drops below the low set point, and is automatically energized again when the pointer rises above the low set point. Manual Reset is a latching action. When the pointer exceeds the high set point, the high set point relay de-energizes and is latched out. It can only pull in after the pointer drops below the high set point and the operator
presses a reset button. In the manual reset mode the low set point relay is likewise latched out until the pointer is above the low set point and the operator presses a reset button.
Installing Auto/Manual Reset
If Auto Reset is desired, simply connect a jumper between terminals 1 and 2 for the high set point or 6 and 7 for the low set point. If Manual Reset is desired, connect a normally-open SPST push button switch to the terminals as shown in the terminal designation diagram. On a dual set point unit, the Auto or Manual mode may be selected for either set point independent of the mode used for the other set point. If both set points of a dual set point unit are connected for Manual Reset, two independent push buttons are usually used. However, one master reset button may be used for both set points provided it is a DPDT switch with no electrical connection between poles.
The 3300 Series meter relays offer a wide variety of applications in control, alarm, and limit use. Photo conductor sensing eliminates all interference with the indicating meter. These relays incorporate an amplifier input which drives a rugged high-torque pivot and jewel meter. Metal-cased “Rugged Seal” construction withstands rigorous environmental conditions. The die cast metal case with a drawn steel plated rear case gives complete magnetic isolation for steel panel mounting. In addition, each controller is moisture, dust, and dirt proof for use in wash-down areas. Failsafe circuitry opens output relays in the event of power failure. Two different sizes, 3-1/2" and 4-1/2", are available in both single and dual set point models. High-gain transistor switch circuitry provides accurate switching with a “dead band” of no more than 0.5% of full scale (F.S.). All DC current meters offer ±2% of full scale accuracy. This style meter is ideal for many other electrical functions.