Below you'll find a list of all items that have been categorized as “Liquid-Level-Controls”
0-15 psi input, 4-20mA output
The Model 451 pressure transducer will convert 0-15psi to proportional 4-20mA signal. It can be used with any pump control system that utilizes a 4-20mA input for level control. The 451 can be mounted in a standard 8-pin octal socket for remote use.
The Model 456-15 Pressure Transducer is designed specifically to meet the rigorous environments encountered in many level measurement applications. This transducer provides repeatable, precise depth measurements under the most adverse conditions.
It has been designed for installation in Class 1, Division 1, Groups A,B,C and D; Class II, Division 1, Groups E,F and G; Class III, Division 1 hazardous locations, when connected to the appropriate Stahl apparatus.
The Model 456-15 features high performance internal signal conditioning. An isolated diaphragm sensor has been incorporated for use with hostile fluids and gases. This sensor uses a silicon pressure cell that is fitted into a stainless steel housing with an integral, compliant stainless steel barrier diaphragm. The sensor assembly is housed in a rugged, compact 316 SS case, which provides for a variety of pressure inputs as well as electrical output connections.
Liquid level controllers generally require a 4-20mA loop current. The loop current indicates the level of liquid in a tank or reservoir, and is usually generated by an expensive pressure transducer or ultrasonic sensor. If you already have a tank with float switches installed, the Model 460D Switch-to-Loop Converter allows you to take advantage of the latest liquid level control, without the added cost of a transducer.
The Model 460D Converter outputs a specific current value as each of the six inputs are closed. Current values are individually adjustable between 4 and 20mA for each switch input. Up to six switches can be used as inputs to all liquid level devices accepting a 4-20mA input, such as Time MarkÕs Model 4052.
The Model 662 Pump Up Control, part of the 600 series line of instrumentation controls, is designed to monitor andmaintain liquid levels. A user-provided 4-20mA current loop represents the liquid level, and output connections are provided for pump control. The HIGH ADJUSTsetpoint, and the LOW ADJUST setpoint, are field adjustable. If the input falls below the low setpoint, the PUMP UP relay energizes, and remains that way until the input rises above the high setpoint. The high setpoint must always be set above the low setpoint. Top-mounted LEDs on the Model 662 show system status. The PUMP UP LED turns ON when the input falls to 10% below the low setpoint, and resets when the input rises above this level. An INPUT LOOP ERROR LED turns ON if the input is outside the 4-20mA range. A Time Mark Model 650 Loop Power Supply (or equivalent) is required to provide the 24 VDC operating voltage.
A Time Mark Model 672-15 Pressure Transducer (or equivalent) is required to provide the input signal.
The Model 663 Pump Down Control, part of the 600 series line of instrumentation controls, is designed to monitor and maintain liquid levels. A user-provided 4-20mA current loop represents the liquid level. The HIGH ADJUST setpoint, and the LOW ADJUST setpoint, are field adjustable. If the input rises above the high setpoint, the PUMP DOWN relay energizes, and remains that way until the input falls below the low set point. Top-mounted LEDs on the Model 663 show system status. The PUMP DOWN LED turns ON when the input is above the high setpoint, and goes OFF when the input is below the low setpoint. The HIGH ALARM condition indicator turns ON if the input rises to 10% above the high setpoint. The HIGH ALARM condition then resets when the input is again less than 10% above the high setpoint. For proper operation, the high setpoint must always be set above the low setpoint. An INPUT LOOP ERROR LED turns ON if the input is outside the 4-20mA range. A Time Mark Model 650 Loop Power Supply (or equivalent) is required to provide the 24 VDC operating voltage. Also, a Time Mark Model 672-15 Pressure Transducer (or equivalent) is required to provide the input signal.
The Model 680 is a user selectable voltage or current simulator. It is useful for the setup and testing of process controllers and indicators with either a current loop or control voltage input, such as liquid level controllers and other devices. The mode of operation is displayed on the top line of the LCD. Either 4-20mA, 0-20mA, 0-10V, or 0-5V. The Model 680 can be set to any one of these four modes of operation by holding down the rotary push-button until the desired mode is displayed. The mode is saved in nonvolatile memory so that the device will power up in the mode last selected. The output signal level is displayed on the bottom line of the LCD. On power up or on changing the mode of operation, the output goes to the range minimum, i. e. 4mA, 0mA, or 0V. The Model 680 offers short circuit protection by actively sensing for any overload condition and limiting output current to 20mA. Overload at the output is indicated by OL on the top line of the LCD and occurs when the output current is 21mA or greater. Signal level is adjustable with the rotary dial in increments of 0.1mA or 0.1V, or you can depress the dial to quickly jump between the minimum and maximum values of the range.
The Time Mark model 430 pump controller is a versatile and advanced liquid level/pump management system. The Model 430 was designed to control up to three pumps with a 4-20mA input. It can also be used to control 2 pumps with a 4-20mA input and backup floats or to simply control two pumps with only float inputs. Alarm inputs are provided, if necessary, and may be disabled through the menu system if not used. Alarm inputs are: SF – seal fail, OT – over temperature, CF – contact failure, and SP – spare (eg. a second seal fail). A relay output is provided for the level alarm (either high or low), depending on pump configuration; PUMP UP or PUMP DOWN.