The model 210 contact resistance test set is a portable line-operated instrument designed to measure the resistance of high current devices, such as circuit breaker contacts and bus bar interconnections whose resistance is normally in the microhm region.The Broman Model 210 Contact Resistance Test Set is a portable line operated instrument designed to measure the resistance of high current devices, such as circuit breaker contacts and bussbar interconnections whose resistance is normally in the microhm region. The model 210 is particularly effective in assessing circuit breaker condition by periodically checking contact resistance, a deteriorating breaker can be detected prior to actual breakdown, thus averting a possible costly outage.

Features

- Easy to operate
- Direct-reading in microhms
- No balancing required
- Self-calibrating
- 10 Year Warranty

Description

The 210 operates on the principle of passing a known current through the test subject and measuring the resultant potential drop across that test subject. Once the current and voltage are known the resistance is calculated electronically and displayed on the microhm meter. Separate leads and clips are used for current and potential measurements using standard four terminal Kelvin connections.

A self calibrating feature is incorporated to permit convenient checking of the overall calibration without reference to external standards.

An auxiliary 100 ampere AC output is provided for demagnetizing current transformers in situations where these cannot be excluded from the test path, or for low level injection testing.

Specification

Input:	120 V AC, 60 Hz, 500 VA
Test Current:	0-100 A DC (0-8 V DC open circuit)
Auxiliary AC Output:	0-100 A AC (0-6 V AC open circuit)
Duty Cycle:	2 minutes on / 10 minutes off at 100 amperes
Resistance Ranges:	0-50/100/500/1,000/5,000 microhms
Meters:	ammeter scales 0-100 A DC voltmeter dual scaled 0-100, 0-500 microhms
Accuracy:	within ± 2% of reading
Dimensions:	12w, 13d, 15h (inches)
Weight:	50 (pounds)

Download Broman 210 Information Sheet (80.7 Kb)

The model 221 digital milliohmeter is a portable line-operated instrument designed to measure low resistance values ranging from 200 ohms down to microhms. The instrument is particularly effective in measuring the resistance of large power transformers.

Features

- Compact Portable
- Easy to Operate
- Fast Measurements of Transformers
- 3 Year Warranty

Description

The BROMAN Model 221 Digital Milliohmmeter is designed for rapid and accurate measurement of low resistance values ranging from ohms down to microhms. The instrument is particularly effective in measuring the resistance of large power transformers which, because of their high inductance, tend to have a long settling time when measured with conventional instruments.

The Model 221 Digital Milliohmmeter provides an accuracy and permanence of calibration approaching that of the traditional Kelvin bridge, but without the necessity of time consuming balancing. The unknown resistance is displayed immediately on a digital meter display. The instrument operates on the fundamental principle of passing an accurately known DC current through the test subject and accurately measuring the resultant voltage drop. The current is established by means of precision shunts used as references and voltage drop across the device under test is measured with the digital millivoltmeter. An elaborate surge suppressor absorbs the transients associated with transformer testing.

Specification

	RANGE	TEST CURRENT (A DC)	ACCURACY± (% of reading + LSD)
	200 W	0.01	0.2 % +5
	20 W	0.1	0.2 % +5
	2 W	1	0.2 % +5
	200 mW	5	0.2 % +5
	20 mW	5	0.5% + 5
	2 mW	5	0.5% + 5
Power:	120 V AC, 60 Hz, 3 A
Display:	0.56 inch LED
Controls:	ON/OFF rocker switch; RANGE selector switch; amplifier ZERO trimpot.
Terminals:	5-way binding posts designated C1, P1, P2, C2
Dimensions:	12 inch (w) x 7 inch (h) x 15 inch (d)
Weight:	15 lbs.
Optional Accessories:	Test leads supplied to customer’s specification

Introduction

The model 221 digital milliohmeter is a portable line-operated instrument designed to measure low resistance values ranging from 200 ohms down to microhms. The instrument is particularly effective in measuring the resistance of large power transformers.

Features

Before repair work can commence on an underground cable, the cable must be positively identified. Many manholes and vaults contain numerous runs of cable and it is imperative that the repair crew does not cut into an energized cable instead of the damaged de-energized cable. This requirement serves as justification for the existence of a cable identifier.

The BCH-2 has the following qualities, which make it an ideal cable-Identifying instrument:

1. It is able to positively identify a de-energized cable that had been cleared at both ends and the risers removed according to Safety Practice Regulations and Local Operating Orders.
2. It is compact and easily handled on poles and in manholes.
3. It can be used with all types of sheathing and protective covering.
4. It can identify cables in the presence of other cables when all the metal sheaths are bonded together.
5. It can work effectively on cable lengths greater than seven miles long.
6. It can work on multiple branch systems.
7. It is battery powered with an eight-hour battery life and is rechargeable overnight.
8. It has a battery state indicator.
9. It can register negative and positive pulses on a zero center indicating panel meter.
10. The transmitter can be shut off by remote control.
11. It can identify cables without cutting windows. It can identify separate dead cables. It can determine if tagged cables are correctly identified.
12. It can "phase" in both directions after a cable cut.

Transmitter

The BCH-2 cable Identifier was developed for use on three phase non-ferrous distribution cables such as PILC belted or XPLE concentric neutral.
The battery powered transmitter generates a 300 V DC pulse which is applied to the "B" and "C" phase of the cable under test, the other end of the cable is terminated by a suitable jumper across "B" and "C" phase of the cables.
The polarity of the DC pulse depends on the direction of the current flow; "B" phase will have a DC pulse opposite in polarity to that of "C" phase

Remote Turn Off

The transmitter has an added feature of "Remote Turn Off". "A" phase is used for this purpose and is usually connected at the same time as "B" and "C" phase.
As a cable is being cut, a momentary short between "A" and "B" or "A" and "C" phases automatically stops the transmitter and removes the open circuit DC voltage.

Phasing

The transmitter has provisions for phasing. After a cable has been cut a diode is switched across "B" and "C" phases inside the transmitter enabling phasing in both directions at the work site.

Battery Charger

The transmitter has a built in battery charger for the two sealed lead acid batteries that are within the instrument case. A charged transmitter battery will give approximately eight hours of operation.

Receiver

The cable identifier receiver is a hand held battery operated solid state device and works in conjunction with an external pick-up coil probe that has been shielded to restrict pick-up to the sensing side of the probe only.

- Compact
- Portable
- High Capacity
- Easy to operate
- Chart recorder connections
- Optional electronic current regulator
- 3 year warranty

Description

The Broman Portable Load Boxes are intended primarily for testing battery banks. They employ a compact array of power absorbing elements mounted in a rectangular duct-like case with a heavy duty fan at one end. Heated air emerges in a concentrated jet which can be directed, through an open doorway, out of doors. Mounted on top of the case is a control box containing a master circuit interrupt switch, loaded switches and ammeter. The load current can be varied by means of toggle switches in increments as low as 1 ampere. Two-way overload protection is provided by a thermal switch which senses overheating and by an air flow switch which senses loss of cooling air. Operation of either of these switches will trip the master circuit interrupt switch.

Also available in 24 Volts @ 250 amps, 48 Volts @ 250 amps, 125 Volts @ 130 amps.

Specification 123XL

Voltage Rating	125 volts DC/AC
Maximum Load Current	110 amperes
Maximum Load Power	14kW continuous
Load Current Steps(@125 volts)	20, 20, 20, 20, 10, 10 amperes (course adjust) 5, 2, 2, 1 ampere (fine adjust)
Ammeter Range	0 - 120 amperes
Current Monitor	1 mV DC = 1 ampere
Auxilary Power	120 volts AC (required for fan)
Dimensions	24H x 14W x 28L (inches)
Weight	60 pounds

Specification 150XL

Voltage Rating	125 volts DC/AC
Maximum Load Current	150 amperes
Maximum Load Power	19kW continuous
Load Current Steps(@125 volts)	90, 20, 20, 20 amperes
Ammeter Range	0 - 150 amperes
Current Monitor	1 mV DC = 1 ampere (915XL current regulator connection)
Auxilary Power	120 volts AC (required for fan)
Dimensions	24H x 14W x 28L (inches)
Weight	65 pounds

The Broman 861 Temperature Calibrator is a portable apparatus designed primarily for checking the winding temperature indicators (WTIs) on large oil-cooled power transformers. The calibrator consists of a thermal unit and a control unit connected by a 30 foot cable. The thermal unit is a thermally insulated cylindrical block of aluminum, mounted on a steel fram, which is placed on top of the transformer under test. The WTI probes are removed from the transformer wells and are inserted into test wells in the aluminum block. The block is heated to the desired temperature by an internal carterage element controlled by the control unit situated at ground level where the WTI instruments are visible and where the associated control contacts are accessible.

The purpose of this transformer tester is to enable an electrical worker to effectively test a transformer at a job-site and to determine if it is safe to energize it.

Download QuickCheck3 Information Sheet (159.4 Kb)

5 kV insulation tester suitable for heavy-duty applications such as large industrial electrical installations, large rotating plant machinery, transformers, switchgear, high voltage insulators and power cables.

Download V5 Insulation Tester Catalog (109.0 Kb)