Series 1251/1253/1254 Welded Chamber Level Control

Min. Specific Gravity 0.40, Pressure to 1250 psig (86 bar), and Temperature to 500°F (260°C)

Leak proof all welded heavy duty carbon steel bodies coupled with snap action or mercury switches provide reliable, long term service for compatible liquids. The use of an external magnet reduces the possibility of magnetic particle build-up inside the armature tube and subsequent loss of operation as may occur with the internal magnet repulsion design. A variety of snap action or mercury switches in SPST, SPDT, DPDT or DPST configurations will satisfy most electrical requirements. These switch assemblies are contained in NEMA 1 general purpose, NEMA 4X weatherproof, NEMA 7, 9 groups B, C, D, E, F, G, explosion-proof or explosion-proof – vapor proof enclosures.

Product Applications

Refineries
Chemical Plants
Power Generating Stations
Water Treatment Plants
Mixing Systems
Scrubbers
Accumulators
Condensate Recovery
Industrial Tanks and Vessels

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Models & Ordering

Specifications

C1-40:: Minimum specific gravity 0.40. Process pressure 1250 psi (86 bar) at 100°F (38°C) to 500°F (260°C).
Temperature Limit:: Ambient Temperature: 212°F (100°C); Process Temperature: up to 500°F (260°C).
Switch Type:: Snap action or mercury. See Model Chart.
Electrical Rating:: See Model Chart.
Wiring Connections:: G, WT or E enclosure: terminal block; EV enclosure: 18" (460 mm) leads.
Process Connection:: Combination 1" NPT/socket weld hubs or flanges. See Model Chart.
Enclosures:: G: painted steel and aluminum; WT: painted steel, aluminum and neoprene; E: aluminum; EV: aluminum and neoprene.
Wetted Parts:: C1 construction. Chamber: carbon steel; Trim: 303SS, 304SS, 316SS and 430SS.
Weight:: 1251: 40 lb (18 kg); 1253: 50 lb (22.7 kg); 1254: 57 lb (25.8 kg).
: Suggested Specifications:
Liquid level control shall be 1251 (1253) (1254) Series with 1" combination NPT/socket weld hub (flanged) process connections. Chamber shall be welded and suitable for operation at 1250 psig (86 bar) and 500°F (260°C) with a minimum specific gravity of 0.40. Circuit shall be hermetically sealed snap action (mercury) switch (SPST) (SPDT) (DPDT). Enclosure shall be general purpose, (explosion- proof) (explosion-proof – vapor proof). Switch mechanism shall be gravity return and shall be activated by a stainless steel float.

Model Chart

EXAMPLE	1251	WT	7810	C1	40		1251-WT-7810-C1-40 Liquid Level Control, weatherproof enclosure, SPDT snap switch, fixed deadband, automatic reset, operating pressure 1250 psig (86 bar) at 100°F (38°C), 1250 psig (86 bar) at 500°F (260°C), side/bottom process connections, 1" NPT/socket weld hubs, minimum specific gravity 0.40.
CONNECTION	1251						One Horizontal and One Vertical 1" Socket Weld or 1" NPT Combination Hub
	1253						One Vertical and One Horizontal Flanged Connection
	1254						Two Vertical Flanged Connections
	1254T
ENCLOSURE		G					General Purpose, NEMA 1
		WT					Weatherproof, NEMA 3R, 4, 4X
		E					Explosion-proof, NEMA 7, 9, Class I Groups B, C, D, Class II Groups E, F, G
		EV					Explosion-proof/Vapor-proof, NEMA 7, 9, Class I Groups B, C, D, Class II Groups E, F, G
CIRCUITS (for electrical circuits see charts A & B below)			48XX				Single Stage Mercury Switch, see chart A
			48XX-XX				Two Stage, Mercury Switch, see chart A
			78XX				Single Stage, Snap Switch, see chart B
			78XX-XX				Two Stage, Snap Switch, see chart B
			78XXHM				Hermetically Sealed Snap Switch, see chart B
			98XX				Single Stage, High Capacity DC Snap Switch, use heat fins (HF) if process temperature exceeds 350°F (177°C), do not exceed 450°F (232°C), see chart B
			98XX-XX				Two Stage, High Capacity DC Snap Switch, use heat fins (HF) if process temperature exceeds 350°F (177°C), do not exceed 450°F (232°C), see chart B
CHAMBER MATERIAL				C1			Carbon Steel Body
				C216			316SS Body
				HFC1			Heat Fins & Carbon Steel Body
				HFC216			Heat Fins & 316SS Body (1251, 1253 only)
MINIMUM SPECIFIC GRAVITY					40		0.40 Specific Gravity (1251 only)
					140		0.40 Specific Gravity & 150# Flange (1253, 1254 only)
					340		0.40 Specific Gravity & 300# Flange (1253, 1254 only)
					640		0.40 Specific Gravity & 600# Flange (1253, 1254 only)
OPTIONS						STW	SS Tag Wired
						01	Breather Only (E-Housing only)
						02	Drain Only (E-Housing only)
						12	Breather & Drain (E-Housing only)
						23720	Fungus Proofing

CHARTS A & B - ELECTRICAL CIRCUITS AND RATINGS

SWITCH TYPE	SWITCH ACTION	ELECTRICAL RATINGS IN AMPS						ORDERING CODE
		AC			DC			SINGLE STAGE	TWO STAGE
		120V	240V	440V	30V	125V	250V	SINGLE STAGE	LOWER	UPPER
CHART A Mercury Contacts	SP-ST open on level FALL	10	5	3†		10	5	-4820	-4820	-21
	SP-ST open on level RISE	10	5	3†		10	5	-4821	-4821	-20
	SP-DT one switch	4	2	1†		4	2	-4810	-4810	-10
	SP-DT two switches E.I.*	10	5	3†		10	5	-4815	-4815	-15
	DP-ST two switches E.I.* open on level FALL	10	5	3†		10	5	-4814	-4814	-13
	DP-ST two switches E.I.* open on level RISE	10	5	3†		10	5	-4813	-4813	-14
	DP-DT two SP-DT switches	4	2	1†		4	2	-4806	-4806	-06
CHART B snap action contacts	SP-DT one switch	12	5	3†		0.5**	0.25**	-7810	-7810	-10
	DP-DT two SP-DT switches	12	5	3†		0.5**	0.25**	-7806	-7806	-06
	SP-DT one hermetically sealed switch	5	5		5**			-7810HM	-7810HM	-10HM
	DP-DT two hermetically sealed SP-DT switches	5	5		5**			-7806HM	-7806HM	-06HM
	DP-DT two SP-DT switches	10	3			10‡	3‡	-9806	-9806	-06
	SP-DT one switch	10	3			10‡	3‡	-9810	-9810	-10

†Available on special order, change 1st digit in ordering code from 4 to 5 or 7 to 8, i.e., -4820 becomes -5820, -7810 becomes -8810, etc.
‡10 amp inductive (polarized) at 125 VDC.
*Electrically Independent.
**Resistive.